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Field Value
Document ID modders-first-mod-tutorial-b42
Version 1.0.0
Status approved
Confidence Medium
Category (track) Modders
Build B42
Owner PZ Knowledge-Base Pipeline
Created 2026-10-07
Updated 2026-10-08
Review due 2027-01-07
Game versions verified 42.20 and 42.21 (API names checked against the Umbrella 42.21.0 stubs; 42.20.0 stubs kept as comparison; code never run in a live game)

Executive Summary

This tutorial walks a newcomer through the smallest useful Build 42 mod: a folder skeleton with the mandatory common/ folder and a 42/ version folder, a mod.info manifest, one client-side Lua file that reacts to a game event and shows floating "halo" text above the player, and an optional scripted item handed to a brand-new character. It then covers local testing, the log file to read when something fails, Debug mode, and packaging for the Steam Workshop.

Every API name used in the code is confirmed to exist in the Umbrella 42.21.0 stubs [1] [2] [3] [4], and every path or key claim is cited to a stub, a documentation site generated from game data, or a pinned pzwiki revision used as a fact source only. The code itself has not been executed in a live game by the author of this document; the Verification Steps section is the test plan. For that reason document confidence is Medium.

Version note: this revision re-baselines the tutorial from 42.20 to 42.21, which reached stable on 2026-09-28 [7]. The API names were re-checked against the 42.21.0 stubs and the 42.20.1 to 42.21 patch notes were read for anything that touches the steps [21] [22] [23] [24]; no step needed to change. Nothing was run in a live game, so the 42.21 check is a stub-and-notes review, not a play test.

Key Takeaways

  • A B42 mod is detected only if it has a common/ folder or at least one version folder; the safe layout carries both, with mod.info and media/ inside the version folder. (cited) (B42)
  • Client Lua lives under media/lua/client/; use a subfolder named after your mod to avoid file-path clashes with vanilla and other mods. (cited) (both)
  • Events.OnGameStart is documented as firing once loading finishes and the player enters the game, which makes it a good first hook. (cited)
  • HaloTextHelper.addGoodText(player, text) shows green halo text and exists in the B42 stubs; the B41 stubs list no addGoodText. (cited) (B42)
  • An item script needs ItemType, and its display name comes from an ItemName translation entry, not from the deprecated DisplayName parameter. (cited) (B42)
  • Read console.txt in the Zomboid cache folder when a mod misbehaves; add -debug to the launch options to start in Debug mode. (cited)
  • Do not keep two loaded copies of one Mod ID; they overwrite each other. (cited)
  • The exact in-game menu clicks to enable a mod are not primary-sourced here and are quarantined as a claim. (community, unverified)

Purpose

To give a first-time modder one linear, minimal path from an empty folder to a published Build 42 Workshop item, with each step tied to a citable fact and each API symbol checked against the pinned stubs. It deliberately goes deeper on workflow than the overview in modders-foundation and defers API breadth to modders-lua-api-surface and modders-events-callbacks.

Scope

Covered: folder and mod.info set-up, one client Lua file, one optional item script, local testing, the log file, Debug mode, and Workshop packaging, all for Build 42.21 (stable), with wiki-sourced layout facts carried forward from the 42.20 revision. Not covered: recipes (see modders-item-scripts-distributions and players-crafting-chains), mod options (see modders-modoptions-pzapi), multiplayer networking (see modders-mp-networking-porting), Mod ID rules in depth (see modders-modinfo-modid-conventions), server-side Workshop wiring (see admins-workshop-mod-wiring), and porting B41 mods (see modders-porting-b41-to-b42). Unstable-branch behaviour is out of scope.

Definitions

  • Halo text — the short floating text shown above a character; here produced through the HaloTextHelper class [2].
  • Version folder — a mod subfolder such as 42/ that holds that game version's media/ and mod.info [14].
  • Full type — an item's module name and ID joined by a dot, for example MyFirstMod.Token [16] [8].
  • Cache folder — the Zomboid directory in the user's profile, holding console.txt, mods/ and Workshop/ [14] [17].

Build Applicability

Build Applies Verified against Notes
B41 (legacy41) No Not verified This is a B42 tutorial; see Delta for what differs. Legacy 41.78.21 was released 2026-08-26 [13]
B42 (stable) Yes API names against Umbrella 42.21.0 (commit 13d01f9) [1]; scripts and mod.info against a ScriptsDocs site labelled 42.21.0 [8] [9] 42.20.0 went stable 2026-07-29 [12]; 42.21 stable followed on 2026-09-28 [7]. Previously verified against the 42.20.0 stubs (commit 58204fc) [25]

What was re-checked for 42.21. The five symbols in the table under "Events and API used in this tutorial" were re-opened in the 42.21.0 stubs and their signatures and descriptions match the 42.20.0 text [1] [2] [3] [4] [25]. The 42.20.1, 42.20.2, 42.20.4, 42.21 unstable, 42.21 stable and forum patch notes were read for changes to mod folders, mod.info, scripts, item naming, events or halo text [21] [22] [13] [23] [7] [24]; the changes that bear on this tutorial are listed in Reference. Statements that cite the pzwiki pages, the documentation-site pages and the ScriptsDocs site are carried forward from the 42.20 revision with no contradicting change found in those notes; they were not re-tested in a game.

Reference

Evidence layer. Facts below are cited; the walkthrough built from them is in Practical Guidance.

Folder layout

The B42 mod layout puts a common/ folder and one or more version folders (42/, 42.1/) inside the mod folder; each version folder holds its own media/ and mod.info [14]. The common/ folder is documented as mandatory even when empty, and at least one version or common/ folder is needed for the game to recognise the mod [14]. The game loads common/ first, then the version folder closest to the running game version, which overrides matching common/ files [14].

Two cache sub-folders matter: mods/ for manually placed mods and Workshop/ for items being prepared for upload, with Workshop/<Item>/Contents/mods/<Mod>/ as the uploaded part, plus workshop.txt and a 256x256 preview.png beside Contents/ [14]. Two copies of one Mod ID in different recognised locations clash and overwrite each other [14].

mod.info

mod.info is the manifest file; its id is the unique identifier used to activate the mod and is not the Workshop ID [9]. The name parameter is the title shown in the in-game mod manager, description and author are free text, and versionMin sets the lowest compatible game version in at least build.major form, for example 42.0 [9]. The file name must be lowercase for Linux and macOS [20].

Lua placement and loading

Lua files go in client, server or shared folders under media/lua; the client folder is not loaded on a multiplayer server, and organisation inside is free [15]. A Lua file with the same relative path as a vanilla file overwrites it, so a subfolder named after the mod avoids clashes [15]. Lua is loaded in the order shared-vanilla, shared-mod, client-vanilla, client-mod [15].

Events and API used in this tutorial

Symbol What the stubs say Build
Events.OnGameStart Client event triggered upon finishing loading and entering the game; callback takes no arguments [1] B42 stubs
Events.OnNewGame Client event triggered when a local player character is first created; callback receives the player and the spawn square [1] B42 stubs
getSpecificPlayer(0) Global returning the player for a split-screen index; the stub notes it is preferred over getPlayer() for split-screen support [3] B42 stubs
HaloTextHelper.addGoodText(player, text) Static helper taking an IsoPlayer and a string [2] B42 stubs
ItemContainer:AddItem(type) Takes an item type string and returns the created InventoryItem [4] B42 stubs

Item scripts

Script files sit under media/scripts/ [16]. Entries live in a module block; the vanilla module is Base, and a custom module name is allowed [16] [10]. The documentation site recommends a mod-specific module over inserting into Base [10]. An item block requires an ID and an ItemType whose allowed values include base:normal [8]. The item's display name is provided through an ItemName translation entry keyed by the full type, and DisplayName is marked deprecated as of 42.13.0 [8] [11]. The Weight parameter defaults to 1.0, and the page warns an item needs a translation entry for weight to work in game [8].

Changes since 42.20.0 that touch this tutorial

Mods gained the ability to write .json files in 42.20.1 [21]. Translation files needed a fix for the percent sign: mod translations should write %% to show a literal % [21], a temporary workaround accepts both forms, and the developers said it will be removed in a future unstable update [22]. 42.21 updated the localization system to allow more translatable strings [23] [24], and its notes say a RuntimeException is now raised when missing translations or missing recipes are detected, in place of a System.err.println message [24]. The notes do not say in which situations the exception fires. The 42.21.0 events.lua stub declares ten events that the 42.20.0 stub does not (AcceptedMedicalCheck, OnFillInventoryContextMenuNoItems, OnForagePool, OnForageRequestZone, OnForageSpot, OnJoypadDebugRenderUIOptionSet, OnPreFillInventoryContextMenuNoItems, OptionControllerButtonStyleChanged, OptionGamepadBindingPresetChanged, RequestMedicalCheck) and drops none; the tutorial uses none of them [1] [25]. The loadstring and loadstream methods removed in 42.20.4 were re-enabled in 42.21; the tutorial uses neither [13] [7].

Logs and Debug mode

The main game log is console.txt in the Zomboid folder, which defaults to %USERPROFILE%\Zomboid on Windows; logs can reveal which mod causes an error [17]. Debug mode is entered by adding -debug to the launch options, with JVM arguments first and ended by -- when present [18]. Lua can be reloaded manually in Debug mode from the main menu [15]. The startup-parameters page is stamped for 42.17.0, older than the current stable [18].

Packaging and upload

The in-game uploader is reached from Workshop, then "Create and update items", and lists the valid mods in the Workshop/ folder [19]. It asks for title, description, tags and visibility, creates or reuses a Workshop ID, and appends the Workshop ID and Mod ID to the description [19]. It overwrites the whole description on each upload [19]. Files removed from a new version are not removed on subscribers' machines [19].

B41 vs B42 Delta

A short delta, since this is a B42-only document; the differences that change the workflow are below.

  • Layout. B41 used media/ and mod.info directly in the mod folder; B42 adds common/ and version folders, and both layouts can coexist in one mod folder [14].
  • Halo helper. The 42.21.0 stub declares HaloTextHelper.addGoodText and HaloTextHelper.addBadText (B42) [2]; the 41.78.16 stub lists only HaloTextHelper.addText and HaloTextHelper.addTextWithArrow (B41) [5].
  • Item naming. DisplayName is deprecated from 42.13.0 in favour of an ItemName translation entry (B42) [8].
  • Script syntax. The ItemType = base:normal form comes from a B42 documentation site [8]; the B41 item format is outside this document.
  • Events. OnGameStart, OnNewGame and OnCreatePlayer appear in both stub sets, as checked by the repository's index builder against the 42.21.0 stubs [1] and the 41.78.16 stubs [6].
  • Wider B41 to B42 differences are covered in modders-porting-b41-to-b42.

Practical Guidance

This is the walkthrough. Each step restates cited facts from Reference; anything that cannot be sourced is in Community Notes.

Step 1 - Create the folder skeleton

Develop in the cache folder, using the layout from [14]:

Zomboid/Workshop/MyFirstModWorkshop/
  Contents/mods/MyFirstMod/
    common/
    42/
      mod.info
      media/
        lua/client/MyFirstMod/Hello.lua
        scripts/MyFirstMod_items.txt
  preview.png        (256x256)
  workshop.txt

Keep only one copy of the Mod ID on the machine (unsubscribe from your own published copy) [14].

Step 2 - Write mod.info

name = My First Mod
id = MyFirstMod
author = Your Name
description = Shows a halo text message when a game starts.
versionMin = 42.0

Keep the file name lowercase [20] [9].

Step 3 - Write the Lua file

Create 42/media/lua/client/MyFirstMod/Hello.lua:

local function sayHello()
    local player = getSpecificPlayer(0)
    if player then
        HaloTextHelper.addGoodText(player, "My First Mod is running")
    end
end

Events.OnGameStart.Add(sayHello)

This uses Events.OnGameStart [1], getSpecificPlayer(0) [3] and HaloTextHelper.addGoodText [2]. The if player guard is a defensive habit, not a documented requirement.

Step 4 (optional) - Add one item and give it to new characters

Create 42/media/scripts/MyFirstMod_items.txt:

module MyFirstMod
{
    item Token
    {
        ItemType = base:normal,
        Weight = 0.1,
    }
}

The module-and-item structure and base:normal come from [10] and [8]. Give the item to a fresh character by adding to the same Lua file:

local function giveToken(player, square)
    player:getInventory():AddItem("MyFirstMod.Token")
end

Events.OnNewGame.Add(giveToken)

This uses Events.OnNewGame [1] and ItemContainer:AddItem(type) [4]. For a readable name, add an ItemName entry whose key is MyFirstMod.Token [8] [11]. The file location of that entry is not primary-sourced here (Claim 2).

Step 5 - Test locally

  1. Launch the game and open the in-game mod manager; enable My First Mod (see Claim 1 for the menu route). The manager lists mods by their name [9].
  2. Start a new game. You should see the halo text on entering the world, and the token in your inventory if you did Step 4.
  3. If nothing appears, open console.txt in the Zomboid folder and look for errors that name your file [17].
  4. Optionally start with -debug in the Steam launch options [18]. In Debug mode the main menu can reload Lua without restarting [15].

Step 6 - Package and publish

Ensure preview.png is 256x256 and Contents/mods/MyFirstMod/ is complete [14]. In the main menu choose Workshop, then "Create and update items", select the mod, fill in title, description, tags and visibility, and upload [19]. Keep a private copy of your description text, because the next upload overwrites it [19].

Common Pitfalls & Troubleshooting

  • Mod not listed. Missing common/ and version folders, or mod.info placed at the mod root instead of in 42/ [14].
  • Edits not visible. Two loaded copies of the same Mod ID overwrite each other; remove the duplicate [14].
  • Nothing happens at start. The Lua file is outside media/lua/client, or has a typo; read console.txt for the error [15] [17].
  • Item has no proper name or odd weight. Missing ItemName entry [8]. On 42.21 missing translations may also surface as an exception rather than a log line [24].
  • Percent sign in a translation string. Write %% for a literal % [21] [22].
  • Case errors on Linux and macOS. Folder and file names are case-sensitive, so common is not Common [14] [20].
  • Ghost files after an update. The Workshop does not delete removed files on subscriber machines; ship them emptied [19].
  • Halo helper missing when testing on B41. The B41 stubs do not list addGoodText [5].

Community Notes & Unverified Claims

Claim 1 — Mods are enabled from a "Mods" button on the main menu by ticking the mod and accepting

  • Claim: Community tutorials describe a Mods entry on the main menu where each mod is switched on (and sometimes ordered) before starting or loading a save.
  • Why unverified: No primary source describing the exact menu route was found for 42.20; the cited docs confirm only that a mod manager exists and lists mods by name [9].
  • Confidence: Medium. Widely repeated and consistent with [9], but the exact clicks are unsourced.

Claim 2 — The ItemName translation file sits under media/lua/shared/Translate/EN/

  • Claim: Community mods place a JSON ItemName translation file in a Translate/EN folder under media/lua/shared in B42.
  • Why unverified: The documentation site names the file type and key format [11] but gives no folder path, and the folder convention changed in the 42.x cycle (wiki mentions a move to JSON) without a primary path statement.
  • Confidence: Low. Path and file naming are unconfirmed on 42.20 and 42.21 (the 42.21 localization-system update is not documented in enough detail to settle it [23]).

Risks & Caveats

  • The tutorial code was not run in a live game during authoring; treat it as checked-against-stubs, not play-tested.
  • ScriptsDocs is community-maintained and labelled 42.21.0, which now matches the stub pin [8] [9]; it was not re-fetched during this revision.
  • The 42.21 re-baseline is a review of stubs and patch notes. The tutorial was not run on 42.21 or 42.20, and its multiplayer behaviour is not covered (see modders-mp-networking-porting).
  • The Umbrella 42.20.0 tag was later moved upstream, so pin by commit, not by tag name [6].
  • The startup-parameters, mod-structure and uploading wiki pages are stamped older than 42.20.0 [18] [14] [19].
  • Whether Workshop/ items load locally without copying to mods/ is not stated in the cited sources; see Verification Steps.

Verification Steps

  1. Pin Umbrella to commit 13d01f9ee58fa48773553920db56d06f0005e7f8 (release 42.21.0) and grep library/events.lua for Events.OnGameStart and Events.OnNewGame [1].
  2. Open the HaloTextHelper stub file in the same commit and confirm addGoodText [2].
  3. Build the folder from Step 1 and start the game; confirm the mod appears under its name [9].
  4. Start a new game and confirm the halo text and, for Step 4, the item.
  5. Place the mod in Zomboid/mods/ instead of Workshop/ to see whether the behaviour differs; record the result.
  6. Deliberately break the Lua and confirm the error shows in console.txt [17].
  7. Re-run python scripts/check_api_exists.py on this file after any edit.

Open Questions

  • Which of Workshop/ or mods/ is loaded for local testing on a stock install? [14]
  • Exact path of the B42 ItemName JSON file (Claim 2).
  • Resolved for the keys used here: the 42.21 stable post and forum notes list no change to item script keys, mod.info or folder layout [7] [24]; still untested in game.
  • Where do ItemName entries live after the 42.21 localization-system update, and when does the missing-translation exception fire? [23] [24]
  • Does OnGameStart also fire when a save is loaded, not only on new games? The stub says "upon finishing loading and entering the game" [1], which suggests yes, but it was not tested.

References

Primary Sources — pinned Umbrella stubs, official announcements, ScriptsDocs.

  • [1] PZ-Umbrella — library/events.lua at commit 13d01f9ee58fa48773553920db56d06f0005e7f8 (release 42.21.0). https://github.com/PZ-Umbrella/Umbrella/blob/13d01f9ee58fa48773553920db56d06f0005e7f8/library/events.lua Accessed 2026-10-07.
  • [2] PZ-Umbrella — HaloTextHelper.lua at 42.21.0 commit 13d01f9. https://raw.githubusercontent.com/PZ-Umbrella/Umbrella/13d01f9ee58fa48773553920db56d06f0005e7f8/library/java/zombie/characters/HaloTextHelper.lua Accessed 2026-10-07.
  • [3] PZ-Umbrella — library/java/__global.lua at 42.21.0 commit 13d01f9 (getSpecificPlayer, getPlayer). https://raw.githubusercontent.com/PZ-Umbrella/Umbrella/13d01f9ee58fa48773553920db56d06f0005e7f8/library/java/__global.lua Accessed 2026-10-07.
  • [4] PZ-Umbrella — ItemContainer.lua at 42.21.0 commit 13d01f9. https://raw.githubusercontent.com/PZ-Umbrella/Umbrella/13d01f9ee58fa48773553920db56d06f0005e7f8/library/java/zombie/inventory/ItemContainer.lua Accessed 2026-10-07.
  • [5] PZ-Umbrella — Candle HaloTextHelper.lua at the 41.78.16 commit fa2e7e1. https://raw.githubusercontent.com/PZ-Umbrella/Umbrella/fa2e7e19799740b57902f1cb4e989225c295c05e/library/Candle/zombie.characters/HaloTextHelper.lua Accessed 2026-10-07.
  • [6] PZ-Umbrella — Umbrella releases (tags 41.78.16 to 42.21.0); pins recorded in this repository's sources/pins.json. https://github.com/PZ-Umbrella/Umbrella/releases Accessed 2026-10-07.
  • [7] The Indie Stone — Build 42.21 Stable Released (Steam announcement, 2026-09-28; located through the Steam news API). https://steamcommunity.com/ogg/108600/announcements/detail/1844751498231307 Accessed 2026-10-07 (host bot-blocks checkers).
  • [8] PZ-Wiki-Modding — ScriptsDocs: item (documentation site labelled 42.21.0). https://pz-wiki-modding.github.io/PZ-API-Docs/scripts/item.html Accessed 2026-10-07.
  • [9] PZ-Wiki-Modding — ScriptsDocs: ROOT-ModInfo. https://pz-wiki-modding.github.io/PZ-API-Docs/scripts/root_files/modinfo.html Accessed 2026-10-07.
  • [10] PZ-Wiki-Modding — ScriptsDocs: module. https://pz-wiki-modding.github.io/PZ-API-Docs/scripts/module.html Accessed 2026-10-07.
  • [11] PZ-Wiki-Modding — ScriptsDocs: Translation Files. https://pz-wiki-modding.github.io/PZ-API-Docs/translations/translation_files.html Accessed 2026-10-07.
  • [12] The Indie Stone — Build 42.20.0 Stable Released (Steam announcement, 2026-07-29). https://steamcommunity.com/ogg/108600/announcements/detail/1839676055882259 Accessed 2026-10-07 (host bot-blocks checkers).

  • [13] The Indie Stone — 42.20.4 STABLE and 42.19.2 UNSTABLE and 41.78.21 LEGACY Hotfixes Released (Steam announcement). https://steamcommunity.com/ogg/108600/announcements/detail/1842212951296601 Accessed 2026-10-07 (host bot-blocks checkers).

  • [21] The Indie Stone — 42.20.1 STABLE Hotfix Released (Steam announcement, 2026-08-05). https://steamcommunity.com/games/108600/announcements/detail/1840310314338766 Accessed 2026-10-07 (host bot-blocks checkers).

  • [22] The Indie Stone — 42.20.2 STABLE Hotfix Released (Steam announcement, 2026-08-05). https://steamcommunity.com/games/108600/announcements/detail/1840310314339441 Accessed 2026-10-07 (host bot-blocks checkers).
  • [23] The Indie Stone — Re-population of the Dead: Build 42.21 Unstable Released (Steam announcement, 2026-09-23). https://steamcommunity.com/games/108600/announcements/detail/1844751498218925 Accessed 2026-10-07 (host bot-blocks checkers).
  • [24] The Indie Stone Forums — 42.21 Patch Notes (topic 101693, first post, 2026-09-23; the long fix lists are abridged to "selected" in the retrieved copy). https://theindiestone.com/forums/topic/101693-4221-patch-notes/ Accessed 2026-10-07 (host bot-blocks checkers).
  • [25] PZ-Umbrella — library/events.lua at the previous pin, commit 58204fc47895ba249592519cedecc7cfbaaebd60 (release 42.20.0; the upstream tag was later moved). https://github.com/PZ-Umbrella/Umbrella/blob/58204fc47895ba249592519cedecc7cfbaaebd60/library/events.lua Accessed 2026-10-07.

Fact-Only Sources (no prose reuse) — pzwiki (CC BY-NC-SA 3.0): URL + revision id; facts only.

  • [14] PZwiki — Mod structure (revision 1443271). https://pzwiki.net/wiki/Mod_structure Accessed 2026-10-07. Fact-only source.
  • [15] PZwiki — Lua (API) (revision 1390433). https://pzwiki.net/wiki/Lua_(API) Accessed 2026-10-07. Fact-only source.
  • [16] PZwiki — Scripts (revision 1442815). https://pzwiki.net/wiki/Scripts Accessed 2026-10-07. Fact-only source.
  • [17] PZwiki — Tech Support (revision 1442989). https://pzwiki.net/wiki/Tech_Support Accessed 2026-10-07. Fact-only source.
  • [18] PZwiki — Startup parameters (revision 1393745). https://pzwiki.net/wiki/Startup_parameters Accessed 2026-10-07. Fact-only source.
  • [19] PZwiki — Uploading mods (revision 1442321). https://pzwiki.net/wiki/Uploading_mods Accessed 2026-10-07. Fact-only source.
  • [20] PZwiki — mod.info (revision 1363935). https://pzwiki.net/wiki/Mod.info Accessed 2026-10-07. Fact-only source.

Secondary & Corroborating — none.

Community & Creator — none.

Further Reading — see the Further Reading section.

Further Reading

  • Unofficial B42 JavaDocs for class and method lookup: https://albion.codeberg.page/PZ-JavaDocs/
  • Umbrella repository (type stubs for editor intellisense): https://github.com/PZ-Umbrella/Umbrella

Related Documents

  • modders-foundation — ecosystem, toolchain and where API truth lives.
  • modders-lua-api-surface — the wider Lua API after this first mod.
  • modders-events-callbacks — the event catalogue behind OnGameStart.
  • modders-modoptions-pzapi — adding player-facing options.
  • modders-item-scripts-distributions — items, recipes and loot beyond Step 4.
  • modders-mp-networking-porting — multiplayer concerns for client/server code.
  • modders-modinfo-modid-conventions — Mod ID and mod.info rules in depth.
  • modders-porting-b41-to-b42 — moving an existing B41 mod to B42.
  • players-crafting-chains — the player-facing crafting side of scripted items.
  • admins-workshop-mod-wiring — using a published mod on a server.
  • meta-style-guide — how documents in this knowledge base are written.

Revision History

Version Date Author Change Approved By
0.1.0 2026-10-07 KB Pipeline (virtual agent) Initial draft. —
0.2.0 2026-10-07 KB Pipeline (revision worker) Re-baselined from 42.20 to 42.21: API names re-checked against Umbrella 42.21.0 (13d01f9); added post-42.20.0 changes (%% in translations, .json writes, localization update, missing-translation exception, loadstring/loadstream); resolved script-key open question. Sources: Steam posts 42.20.1, 42.20.2, 42.20.4, 42.21 unstable and stable, TIS forum 42.21 notes. —
1.0.0 2026-10-08 Orchestrator (KB Pipeline) Approved and frozen — release kb-release-2026.10.08 (42.21 re-baseline; validated against 42.21 and 41.78.21, Umbrella 42.21.0 @ 13d01f9). Content is the reviewed 0.2.0 text. Project owner (user instruction 2026-10-08)