I had trouble with the PLE version at work when switching between 16 and 32 bit - the mainpulator tools were a bit screwy. Saying that its an old radeon card at work and that is more than likely causing problems.
My laptop is a mobility radeon 9700 and I found I had to disable triple buffering (using the radeon tray tools) to stop glitches happening. Might be worth checking out depending on your card