Steps I took that resulted in the problem:
Dowloaded Fritzing0.9.3b.dmg from fritzing.org
Opened the dmg and dragged the Fritzing app to my applications folder
Started Fritzing app from my applications folder.
Fritzing starts downloading libraries and then comes up with the main screen.
Then after a few seconds the app closes and I get a msg from OSX saying that the app has stopped responding.
What I expected should have happened instead:
Fritzing to keep running.
My version of Fritzing and my operating system:
Fritzing 0.9.3b, Mac OSX 10.7.5
NB: I tried version 0.9.2b as well to check if that had the same problem. That version runs fine.