what exactly happened: I was working with the program, I left it running on one monitor while I opened a youtube video on the other monitor. I saw the program just disappear, though the tools and brushes stayed on the screen. Upon checking Task Mgr, I found the program status to be 'working', but nothing was visible on the screen (except as mentioned above). I have uninstalled and reinstalled the program and I get the same result: no menu bar, no working area. Only tools and brushes.
What else can I tell you?