As for whatever I "have running", it occurs even when Finder is the only app active (confirmed AFAIK by ONYX insofar as what's started at logon). Insofar as "why shutdown" I know that power drain occurs even with a short time away. However, I'll try verbose shutdown as you suggest, to see what's going on. Thanks for all your help, in spite of your other remarks. I'll leave it at that.
12/3/12 at 7:15am