I never had problem with GPartEd before, even it's not 1.0 yet. So this surprised me. It happened when I was resizing a cloned partition to fill a bigger drive. Two partitions: 1 NTFS, 1 FAT (IBM diagnostic partition). So I moved the FAT to the end of the drive and expanded the NTFS. Once I clicked "Apply", the GPartEd window went away. I kinda scratched my head and opened a terminal window. top showed gpartedbin is hogging about 97% of CPU. I waited for a while. Nothing. Guess it's stuck. I tried opening another instance of gpartedbin, and it showed partitions unchanged but NTFS having unreadable content. Crap! I had no choice but to kill the thing. Luckily things seem to be OK after restart.
Eventually I got the job done with Acronis. Not sure if this is a bug.