First, let me state, I'm not a programmer. However, I do know Win2K quite well and have run into a number of programs that react the same way your software is reacting in non-admin accounts.
It really depends on what processes your software depends on in Windows 2000. There are a number of process files that are limited to being 'edited' only by admins. This is a security issue in Win2k - and I would expect in WinXP also.
MSVCRT.DLL (Microsoft C Runtime Library) is an infamous one for causing this, since a number of programs rely on coding this file for its executing purposes.
My workaround for this was to use the '
RunAs ' command in Win2k, which allows the user to run the app as an admin, from any user login - but this doesn't have the professional look to it and probably isn't what you would look to as a permanent solution.
Another solution may be to include the process files, that are normally included on the OS, actually with the program itself - therefore, the software will load its version of those files, instead of the protected ones in Win2k.
I also ran into this website : called
Walls
that I think is addressing your issue - you may check it out for some ideas too.
Hope this helps atleast a little bit!