I have been trying to run Stratego on my CC and keep running into strange screen issues. If anyone is familiar with this game, this is what's happening. The ACCOLADE animated color logo shows up fine, but then the Stratego title screen pops up in B&W. The board, pieces, and info windows for the game then appear and the graphics are all scrambled. What's really strange is that the Apple Menu bar has changed from the rainbow Apple icon into a Black Apple icon. I've tried the game on my iMac G3 in OS9 and it runs perfectly there.
My CC has an LC575 Logic Board with a 68040 (with Math CoProcessor). I have not attempted the hi-res screen mod, so I am running at the CCs native res.
The sort of issue you are describing is often attributable to having a color depth set that is not supported by the game. Color depth is the setting that controls whether your Mac is displaying 256 colors, thousands of colors or millions of colors. A CC is limited in this regard by how much VRAM it has.
This might not be the problem, but you could try changing the color depth on your CC (if possible) and seeing what happens.