Thanks for the quick reply!
I had meant the terminal, and wasn't aware of the F12 bit. However, for some reason on the installation in question, F12 didn't seem to do anything. It works fine on all my other machines (also Linux).
Oddly, I managed to get it to work by wiping it off, removing the ~/.config/sozi directory, and re-installing. But then, after a few times running sozi, it stops working again --- can't load SVG, F12 does not work. Grrrr. Now, the same procedure does not yield a working installation. So I have two questions:
(a) Does sozi keep other "state" around somewhere, outside of ~/.config/sozi and /opt/Sozi?
(b) Are there any other ways of getting diagnostics, such as a way to get it to dump stuff onto the terminal or some kind of log file?
Thanks, and sorry for the trouble.