I figured out what the post count problem had been: I'd installed some behind the scenes mods in the copy of the forum that runs in Linux on my computer, and rather than install them all over again in the scripts for the real forum, I'd uploaded the modified scripts for the dummy forum. Now, why is that significant? Well, I'd forgotten that a few days before on the dummy forum I'd been testing an already built in system feature that allows us to set zero post counts for any of the boards and those settings were still in effect on the dummy forum. So, after I'd uploaded the scripts with those settings, whenever someone made a post in any of the boards that had zero post count set, their post count didn't increase. Oops.
However, I've since removed those settings and I've written a script that recounted everyone's post counts, so they should all be accurate now. But I think I may need a vacation to prevent anything like that from accidentally happening again.
Hmmm...maybe I'll take a few days off to finally watch the seven Buffy and three Angel episodes that I still haven't seen because I never took the time away from the forum to watch them when they were originally on...