I'm afraid the time has come to put ROXTerm to sleep. I've had a look over the code and latest GTK API and I'm pretty sure there is no quick fix for bug #125, in fact there is even more code relying on the old geometry than I realised, and I could end up messing around with it for months trying to get all the sizing features right. The only satisfactory solution would be a major rewrite, which isn't really justified by whatever distinctive features ROXTerm offers over anything else that people (including myself) are relying on. With such a big bug in the way it doesn't seem worth tackling the other outstanding issues. Apologies to all the people who have taken time to report and discuss them.
There is one potential killer feature I can think of, and that's to integrate the functionality of something like tmux or screen with remote capability, but I think that would require at least major support from a reworked vte, and I think it's over-ambitious for me.
So, unless anyone else wants to take this over (seems unlikely), I'll soon start doing things like getting it removed from Debian.