First, I have to apologize to floridave. Between equipment failures at home, trying to lock down a Wordpress gallery, trying to get an online business up and running, Gallery3 failing, and a hosting company whose call center is overseas ... and we all know how well that works. I was testy, tired, grumpy, and didn't know which cat to kick (metaphorically speaking that is).
So, floridave, I apologize. Let me tell you why.
I installed Gallery3 for a third time. This time I tried to do it right. I manually created the database and did an upload to avoid the autoinstaller. Damn thing screwed up right away. I got another of those unknown theme pager errors too.
Make a long story short, I found a hosting company that gives you a one month free trial. I decided to try an experiment. I uploaded Gallery3 + extra modules + extra themes, created a database, and ran the install. I changed my theme right away and proceeded to upload pictures. Now, I did get "unable to process" messages, but you know what? The logs are clean.
Gallery3 is snappy, It is behaving every inch the way I had expected it to behave. Pages load quickly. If I wasn't so tired I would be ecstatic.
So, I'm back, and damned happy about it.
... edit ...
I forgot to mention that, yes, it was the stupid hosting company's fault. Their shared mySQL is way over shared. Gauging by all the other complaints I was not the only one having problems. I just need another say and I will everything ready at the new host so I can "flip the switch" as it were and put the other host behind me.