Thanks for the advice! It seems really snug in there... I tested it in the store for fit before I bought it, but maybe I was just being hopeful. (My default mode.) but having seen the shaving method solve a similar problem I'll give it a shot. :3
Don't worry, I've already lost all my data once when I removed the batteries. Turns out my "BIOS" (not sure what it's called in a calculator, haha) battery was bad, so I lost all the programs. It's all good though, it was just awkward learner noises anyway. What's the typical battery life of a TI-82 running HT? Mine lasted for about four hours... seems kinda slim. Maybe my batteries were old to begin with though.
Anyway, glad to hear HT isn't mothballed! It's a great program and I have this feeling your hard work won't go unappreciated.