Thanks to everyone for your thoughtful comments.  I don't do this full time, what little creative time I have to work on Poser has been sucked-up the past two weeks by this infinite rendering do-loop:

Read forum => Tweak settings => Render => Come back later => Render still sucks

Repeat until insane! LOL

The tip about setting GC to 1.0 in the custom IBL settings is a new one I'm trying out now.  Perhaps when I get this figured out I'll start a thread entitled 'Successful PP 2010 Lighting/Render Settings", and make a record of my successes, encouraging others to contribute theirs.

Thanks again...

Danborn