Ok, unfortunately my discovery above was only a partial solution. Again, I just lost my ability to select anything (not just points in the glyph window, but even selecting a glyph to edit), and had to quit FontLab and reload it to continue. Hitting 'Return' did open the glyph window, however. Just couldn't select any points, and Outlines was not locked.
At least I haven't managed to crash this version of FontLab, so that is a step forward. The old version (5.0.4) used to crash several times a day, depending on what type of work I was doing.