reverting to older version of Parallels

Hi,

I have an older copy of Parallels 4 for my older MacBook (32Bit 1,1). I recently tried to upgrade only to find that my old machine/OS will not accept the newer version. I tried to uninstall it and then reinstall my working copy from TimeMachine replacing all the pref files I could find, the VM from my documents folder and the .app files from the applications folder. Have even tried to reinstall with original disk. No dice. Anyone know the solution?

Thanks