After having overcome the issue reported with Bug #1172375 and having had it generally working, this morning it again showed the Login Screen and subsequently the entire Windows Desktop rather than the application in its separate window only. -- Basically I encountered the issue reported with this bug again. -- This time I was very certain that I haven't changed anything on my system since. However looking closer at my guest OS, Windows 7 Ultimate 64-bit, I then saw again a pending service fix installation, which required a restart. After having restarted Windows 7 Ultimate in order to install the pending services fixes, it all started to worked again.
Current Conclusion:
It seems, whenever Windows is being updated and/ or has a pending service fix installation, it presents the user with the entire desktop rather than opening the application and rendering it in its own window.
After having overcome the issue reported with Bug #1172375 and having had it generally working, this morning it again showed the Login Screen and subsequently the entire Windows Desktop rather than the application in its separate window only. -- Basically I encountered the issue reported with this bug again. -- This time I was very certain that I haven't changed anything on my system since. However looking closer at my guest OS, Windows 7 Ultimate 64-bit, I then saw again a pending service fix installation, which required a restart. After having restarted Windows 7 Ultimate in order to install the pending services fixes, it all started to worked again.
Current Conclusion:
It seems, whenever Windows is being updated and/ or has a pending service fix installation, it presents the user with the entire desktop rather than opening the application and rendering it in its own window.
I hope I got to the bottom of it now :-)