Problem occurs on both Windows and Mac in the qt.py example running with PySide 1.2. Process hangs when quitting app. This needs further debugging to figure out what call is causing the issue - whether it is cef.Shutdown.

Issue on Windows reported on the Forum ("python.exe" has stopped working):
https://groups.google.com/d/topic/cefpython/PPPqWlRGx-8/discussion