it's a little late now, but trouble like this with pm is not unusual.
best results come when you move off as much data as possible, defrag, and then give pm only one function to perform at a time.
in other words, if i wanted to expand my c into d territory, i would (assuming your c is a primary & your d is a logical drive in an extended partition):
1. move off as much data as possible and empty trash, delete all temp files, and ie temp files.
2. defrag both partitions & create a ghost image of c
http://ghost.radified.com/3. shrink the d logical from the inside
4. reboot/execute operation
5. shrink the extended partition from the inside
6. reboot/execute operation
7. extend the c primary to fill the unclaimed space created by the 2 previous steps
8. reboot/execute operation
i have done this before myself, with no problems .. but i know many who weren't so fortunate.
most people try to do steps 3-8 all at once.
you want to make it as easy for pm as possible.