Toonboom storyboard Pro 4 total Bitmap and Vector layer failure to draw in.

Hello everyone. I have Storyboard Pro 4 and yesterday morning after an hour or so of using it I could not draw in Bitmaps or Vectors. Just not responding. Don’t think it’s my pen and tablet (it’s a Yiynova) as the mouse won’t ‘draw’ either. Downloaded Trial version of Toonboom 5 and weirdly the same problem persists but I can only draw in Vector layers but cannot do anything in Bitmap layers. So has anyone out there had this problem and if you could advise me what I could do about it please? Thank you very much in advance if anyone can help.

This might be an indicator that the system’s graphic card ran out
of memory. If you reboot the computer, does the problem correct
itself?

Also try closing unnecessary programs and web pages.