The color issue in that game is most likely related to DirectX 8 (at least I think it's DX8, could be wrong) not playing nicely in Wine in general. Not something I can debug all that easily :)
Yeah, IIRC there was something about shaders being the problem, no corroboration. It very well could be shaders (I wouldn't know either way). If I were you trying to debug this further (or if I was just giving you work), I would start by getting a clean trace:
1) Install on a working system (so Windows)
2) Download current Windows' version of apitrace (recently updated)
3) Trace game. If successful goto next.
4) Replay trace under Windows. If successful and clean trace goto #7. 5)
Failed trace then try with PixWin.exe (historical SDK download). 6)
Replay trace under Windows. If successful and clean trace goto #7.
7)Replay trace under Wine. If correct replay then success, new info, link trace to bug report. If rainbow replay then failure, new info, link trace to bug report.
I've received, I can assume it's either unimplemented shaders or the shaders are simply stubs and would need to be fully implemented.