I tried it with Samsung Focus 1.3 Mango.
The Backup Worked nicely but was stuck forever, Then I pulled the battery out but still stuck on the Backup Screen.
Next I used your tool to restore and for some reason it rebooted the phone and it was out of stuck mode.
Then I got the error message of Backup Failed like you said.
I had no courage to try restore but the log says backup was complete thats all. So it works but probably Need to make it even smoother.
Can you send me your "log.txt"?