I arrived home to Emplode sitting at the home screen and I just threw another album over. The database rebuild took about the same length of time as before... about 12 minutes.
Next thing I'm going to try is running the fidsifter via Hyperterm and the serial port, but not tonight.

Thanks, Mark, for the tip about the error message.
Thanks, tanstaafl, for sharing your .bat file.
I should learn more about how to take it farther.