Short test track did not help, most likely because of low battery. The sound test for the one engine yielded sounds staying on for no more than 4 seconds, so the battery is charging now. Another engine that did retain the new address from the prior work has sounds staying on in excess of 6 seconds.
Looks like you guys nailed it. I'll report tomorrow on how the re-charging works on the other engine.
Thanks to all for you input!
Dave