OK, not that anyone would ASSUME that there was a problem with UBB software from my post above...
However, I feel obligated to post my results *cough*or mistake*cough*.
I forgot I'd already upgraded my test environment to 7.5.x. So, our /ubbthreads directory was different. Once I downloaded a fresh copy, it just worked. I even shut off mysql on my system to verify.
So, things are looking good.
Thanks for the advice Ruben. I'm liking this approach more and more.