okay, it seems that I simply needed to "deactivate" the post thumb 2.2 plugins I'm still using for thumbnails (these are the pre-hacked versions of the thumbnail apps, of which there are 3 plugin pieces). Disabling those three revisited/library/widget did the trick.
Obviously in debugging, it was fairly obvious after I looked at the two sites on same server running same templates, and all the same plugins - except this one.
THANKS AGAIN Charles for all your hard work. FYI, I did end up using the Tim's thumbs and hacking it to do what I needed in place of the add-on I paid you to wrangle for me. More donations coming.
Next wish list would be a "highly optimized" version to use the least amount of system resources possible. :-)