I've heard of one other program on Win2k, something to do with the program crashing in the options sections. I have a win2k machine here that I am going to do some more testing on. Right now my guess is that there is an updated OCX or whatnot with Win2k that does not get overwritten during the install(as it shouldn't), but that is incompatible with the versions used to make the program.
What version of Win2k are you using? Pro, Server, Adv. Server?