Can not close Qt Creator

When running Qt Creator with a settings files originally created by Qt Creator 1.3.1 I end up with a creator that ignores all requests to close the window.

This means:

• File->Quit is ignored
• The close button on the window is ignored
• The close button in the windows panel is ignored

To close the window I have to kill the process in the task manager.

On Linux this scenario even triggers a crash.

Opening files, etc. works fine.

Attached you will find the settings files used by my creator.