Thanks for the info about 2.1.1 vs. 3.0.0.
Okay, I have "upgraded" back to 2.1.1 following the instructions that EvilDragon posted earlier. I copied everything except gp2xboot.img to the SD card and installed 2.0.0, then I upgraded to 2.1.1. The GP2X is running 2.1.1 and is working fine, but...