Hi. Can we separate out the issues with Express and FBX - they use completely different methods of recording the screen, so the issues may not be related. So...
For Express, this 'top left corner' thing isn't something we've heard of before. Can you reproduce the problem, then go to the Help menu -> Support -> Report a Problem to Blueberry. And give us a quick description of the problem so we know its you and what you're trying to record.
For FBX - you're still talking about RPG Maker? Still wondering about options to make these non-DX/OpenGL games recordable.