Memory at 0x0000000 ?? That's not exactly a valid memory address

.
An instruction at 0x10001df7 (memory address of the instruction) made a call to a memory address that doesn't exist. That's a software problem within twxsync, or something else that's causing twxsync to be unable to access it's normal memory space.
First thing I'd do is kill all non-crucial processes (firewalls, anti-vir, etc). Then I'd look at the OS. Then I'd look at twxsync and see if you can replicate the problem on other systems.