Anyone experiencing crashes that can't be traced down to anything real should try playing the game by limiting it to 1 CPU core, on systems with 4 or more cores some may have luck with limiting it to less than half of the cores.your.
... Personally this occurred as spurious crashes (in nvd3dum.dll which supposedly indicates bad GPU driver) until it finally became rather consistent when trying to protect the bloodtox tank.

The game is also one of the few games truly incompatible with 64 bit version of XP, so you're out of luck there (compatibility mode nor anything else will help you).