ProAudio9/XP unable to save files

Hello,
I upgraded my PIII/667 machine to XP and reinstalled PA9. It ran fine for a while but recently it won't let me modify files and save them without crashing. I had recently installed a new driver for my Korg NS5R module connected via com1 port. Sometimes it works othertimes it doesn't. I can save a midi format 0 file as a .wrk file but if I try to save it as a format 0 file the system does not respond and it hangs. Iwould consider upgrading but I can't afford new hardware and new software which I would need if I go to Sonar. I wonder if anyone has gone to Home Studio from Pro Audio without much difficulty?