Well, the Windows->Outline workaround worked for me. It made the program super-clunky, but okay.
Now, though, after spending some time working, I get a "Signal #11" error, and apparently my save file contains whatever is killing the program, so whenever I try to load the file I was working on, it crashes. Which means that my work is effectively totally lost.
It's clear that this program is not ready for actual usage; I'll move on to something else.