Maybe you guys have figured this out, but in case you haven't:
I had this same problem when I loaded oceanlog on a new computer. Every time I started the program it would go into "not responding" without taking any input.
I then connected my dive computer to the PC, then started the program and it came up without issue.
I then setup the divelog, and downloaded the dive log from the dive computer, saved it off, no issues.
Now the program starts without issue whether the dive computer is connected or not. It must probe for the USB device when it first loads.
I'm running 2.3.7 Built 09.21.12 (which is the beta version) computer: Atom 3
(I also discovered that if the battery is low, it will not be seen by the PC's USB device even though the dive computer still seems to work normally).
fj..