Baldur's Gate previews

Three distinct official previews are useful local-only Infinity Engine fixtures. None of their payloads may be committed to this repository; their pinned sources and extraction recipes live in test/candidate-corpus/manifest.json.

Runtime findings

The Chapters build has two startup gates absent from the other packages:

• It calls GetSystemDefaultLangID, then GetLocaleInfoA(LOCALE_SYSTEM_DEFAULT, LOCALE_SENGCOUNTRY, ...), and rejects any result other than United States or Canada. Returning the old generic locale placeholder therefore produced its genuine Wrong Version dialog. LOCALE_SENGCOUNTRY now follows Win32's size-query and insufficient-buffer contracts and returns United States in both ANSI and UTF-16 forms.
• It imports WinSock 1.1 through WS2_32.dll by ordinal. Ordinals 115 and 116 are WSAStartup and WSACleanup; the loader previously exposed that ordinal table only for WSOCK32.dll. Treating both basenames as aliases clears the <ord> dispatch failure and reaches the real JigSawedME Infinity window.

Both playable builds use a borderless 640x480 DirectDraw window positioned at 0,-23. Their cinematics accept Escape/Space through the ordinary renderer keyboard path. The interactive demo's main menu changes from SINGLE PLAYER / MOVIES / QUIT to NEW GAME / LOAD GAME / BACK after a click at (320,265); the Chapters preview exposes the same interaction under its "Baldur's Gate Abridged Chapters I & II" artwork.

Starting New Game in these old builds performs a large synchronous first load of Gui.bif, Creature.bif, CHAAnim.bif, and the script resources. The decoder thread also suspends itself while idle; self-suspension now yields to the scheduler and resumes only after another thread calls ResumeThread.

Two Infinity Engine request handlers set a state-transition flag and then wait for the outer game loop to clear it. A cooperative guest cannot run that outer loop until the handler returns, so each preview has two verified executable patches that jump over only those waits: one for New Game / Character Generation and one for Accept / area entry. The outer loop then performs the requested transition normally. The patches are executable-hash-specific in practice and byte-verified before application; a different build is rejected.

The local acceptance walks Gender, portrait, Race, Class, Alignment, Abilities, Skills, Appearance, Sound, and Name; accepts the character; dismisses the Prologue panel; and captures Candlekeep. Its in-world assertion requires a detailed 640x480 frame plus the selected character's green circle in the play area, so a cinematic, main menu, or Character Generation panel cannot pass.

Reproduction

Fetch all three candidate IDs, then run:

node test/test-baldurs-gate-demos.js

The test compiles one source snapshot, pins each executable hash, rejects runtime failure markers, checks detailed 640x480 output, and requires both playable builds to reach the in-world scene after injected keyboard and mouse input. Screenshots are written under build/local-candidate-smoke/baldurs-gate-demos/.