OK, I knew it had to be simple and that a little bit of sleep would help. I forgot to update one site-specific setting after moving the app from the dev environment to production. What's ironic is the particular setting in question is part of the code I submitted to the calendar module to fix the very problem I was having. D'oh!
Poop. It seems the calendar isn't working properly on the live site, yet is working just fine on the development site. It's a bit too late (or early) for me to figure out WTF is different. Hopefully it isn't a big deal and it's just because I'm tired that it isn't obvious to me right now.
I've just made the newest incarnation of Gothic BC live. I've been working on this since late October and I really don't know how many hours I've put into this to get it to a workable state. There is plenty more work to be done, but hey, I've been plugging away at this for almost 10 years now and there is always more work to be done.