Well, that took a while.
I decided I needed to examine the problem with the Windows nastybug (losing UI updates). It appears to have gone away. But only after I took apart the internal workings and rewrote them, so there is a fairly high probability of my having broken other things.
Watching for lurking bugs for a while, I think...
Whilst the previous version was considered a "Beta testing" release, I would say this is back to "Alpha test", at least for this release. I will be using it as it seems to be working better on Windows than the previous versions and I will fix any bugs I spot but, as ever, drop me a line if you spot anything I miss.