There is something with the application's message handling system... When the app hangs for some reason, it becomes completely non-responsive for the OS. Example:
Help -> Updates...
Checks for updates, then, clicking OK tries to open the Welcome Screen which nearly always cause hang. In this case only Task manager -> Processes -> corelDRW.exe -> End task helps or a user logof...
Other applications behavior is a whiteout, then automatic app close.