BINGO! Found my problem! Told ya I don't give up, David. LOL I opened up my WinFW Notifier GUI (I'm new to that SW, too, and never looked at the log) and found a log that showed me connection attempts today. There were a bazillion attempts to get out by a file in the Avast Setup folder called instup.exe. The moment I gave it outbound access, the GUI updater worked just fine.
Consider this one resolved! Peggy is a happy camper now.