I have one for rct2 that works in winxp, one of the few I've found. When I get home from work and am on my computer at home I'll stick it up on one of my servers somewhere and tell you how to d/l it. (If you haven't already found one by then).
Try doing a search for Beast Trainer for RCT2 (I think that's the name).
It allows you to make the rides more reliable, add peeps, add cash, etc...
It is also very easy to use. Simply load RCT2, load your game scenario, then hit your ALT key (to return to your desktop) and double-click on the trainer. Then alt-tab back into the game and it is working.