Format

ARCV — COLONIZE.$00

ARCV — `COLONIZE.$00`

448,483 bytes holding the game’s original, pre-patch colonize.exe. Solved; colwin does not extract it.

Container

0x00  "ARCV"
0x04  WORD   version               0x0110
0x06  WORD   offset of first CHNK  59
0x0c  BYTE   member name length    12
0x0d  char[] "colonize.exe\0"
0x19  DWORD  uncompressed size     0x0011EE00 = 1,175,040
0x1d  DWORD  compressed size       0x0006D798 = 448,408
...
0x3b  "CHNK" + WORD version + WORD header size (16)
0x4b  payload

Exact: 75 + 448,408 = 448,483, the file size. The uncompressed-size field was not identified until after decompression produced exactly 1,175,040 bytes — the field and the result agree, which checks both.

Payload: LZHUF

Adaptive Huffman over an LZSS window. Nothing here was guessed: SETUP.EXE carries the ARCV reader — its strings include Not an ARCV file, Incorrect ARCV version and Incorrect file checksum — and every constant came out of it.

Routine in `SETUP.EXE`	What it is
`1008:0809`	`StartHuff` — `freq[i]=1, son[i]=i+T, prnt[i+T]=i`
`1008:08b5`	`reconst` — halve frequencies, rebuild the tree
`1008:0a0f`	`update` — `MAX_FREQ = 0x8000`
`1008:0b23`	`DecodeChar` — walk `son[]` from `son[R]`, one bit per level
`1008:0b8d`	`DecodePosition` — `d_code[]` / `d_len[]` at `DS:0x4ee` / `DS:0x5ee`
`1008:0c49`	`Decode` — 4,096-byte ring prefilled with `' '`, `r = 0xdc3`

Parameters: N = 4096, T = 573, N_CHAR = 287, R = 572. T = N_CHAR × 2 − 1 holds exactly, and 287 = 256 literals + 1 end marker + 30 length codes, which is what fixes the alphabet. A match code c copies c − 0xFF + 1 bytes.

What the pre-patch binary shows

	shipped (patched)	recovered (pre-patch)
module, linker, target	`COLONIZE`, linker 6.1, Windows 3.10	identical
imports	WING, COMMDLG, GDI, KERNEL, MMSYSTEM, USER, WIN87EM	identical
segments	34 (19 code)	33 (18 code)
size	1,227,264	1,175,040
`Assertion failed` strings	5	0

The patch added a code segment and added the asserts — consistent with README.TXT, which describes it as fixing recurring lock-ups.