I've tried to put together some technical information for you super-hackers.
BUG! -It appears there is a bug in the kernel on this unit involving the save to disk routine. The load routine works fine, but attempt to save anything from BASIC or any ML program which uses the kernel save routines, and the file will be larger than expected and usually corrupted. The good news is that it can be fixed. There are two solutions. One solution is to flash the kernal with a patched version. That is what I did. The other solution, if you aren't up to risking a flash, is to use the kernal-patcher program and simply install a patched kernal in upper memory and run from that while you are doing anything requiring the use of the save function. When you power off and back on, you'll be back to the original kernal with the bug.
It is also worth mentioning that the power switch cuts the ground, not the +5V as one might think. The reason is that there is a small resistor designed to drain any current from the capacitors on the board. The idea is that when you shut it off, the memory has to be dumped before you would be able to boot it back up properly. So the way the power switch is wired up is for that purpose. However, people have found that if you connect something else up to the board (anything, video cables, disk drive, etc) that shares a common ground you might find the unit mysteriously stays turned on.