Went back to an earlier save and tried again ... with success ... whew!
Not sure if it made a difference, but the time I had the problem
the DK was party leader - the second time I tried Hero as leader.
Unfortunately, I've tried several times to re-creare the problem
with the saved game without success ... I'm suspecting a memory
leak somewhere since (in my experience) the strangeness seems to
increase the longer my game-playing session is ...
Anyhow ... save often ... as is continually suggested!
=Gneen