I guess it had to happen... After transitioning my build environment to the Windows 7 DDK PPJoy will no longer support Windows 2000. The installer will refuse to install on Win2K. A word of warning: do not try to manually install the drivers on Win2K - this will cause a nasty bluescreen on reboot.
[Anybody wanting to use PPJoy on Windows 98 or 2000 should use version 0.83 or earlier.]
On a related note: I've now finished a test version of the new installer (which can automatically enable test mode) - now to test it on Win2K, XP, Vista, etc with different configurations to ensure it "does the right thing". Unfortunately this will still take while.