Game 3.02 crashes on start before even disk check. Vanilla runs normally. Init log tells:

[1794.343] ERR: InitWinApp() failed, exiting
[1794.343] ERR: CIV Init FAILED, exiting

Athlon XP 1600+, Windows XP SP2, GeForce 7900..

Is there any more useful info, I can give?

Have you tried a reinstall?