In the Windows Catalogue screen, I always get a windows that is not there. In this case, it's the PortableApps.com PortableFileAssociator: http://portableapps.com/node/15583.
Is seems to be an AutoIt program that even when it's minimized in the system tray it still shows in the Windows Catalogue. Obviously, clicking on this windows doesn't do anything. Check it here, is the windows under the 2 notepads:

Probably, the problem lies in the app side and it might not be behaving very well, hence why you still show the Windows as available. In any case, is there some way from your settings (I've tried rules without luck) to be able to not show that window in the catalogue?
Thanks!