Done, Vlk, thanks.
Interestingly, I rebooted and tried manual updating after that – and it did succesfully “downgrade” a couple of sub-versions from what you say was probably a lab-only-version. I forget what I started with, but it’s now showing as 4.1.418.
The most interesting thing was, in the process it had to download and install from scratch (saved the original INI though, thank heavens), 2 megs plus. I guess that’s deliberate in case there’s a major foul-up with one of the lab versions, easier to start over from a last-known-good point.
Thanks again, and best,
Mike