The adapter is Radio Shack part number 273-1815. This is a high current adapter that can deliver 3 amps. The FotoShow is center positive. The device is pretty fast switching between pictures on the screen because it is actually showing you the 640x480 reduced shots that it made. Doing anything with shots from a 3Mpixel camera is a 20 second operation though, indexing that shot or editing or zooming in on that shot will take that long.
Smaller shots are faster.
Copying shots from a CF card is pretty fast. If you are going to put shots on the FS just for the purpose of just displaying them, there is no sense in putting on full sized shots, especially if your shots are large. This will just take up extra space on the drive. In testing, I can't see any quality improvement between shots that I resized over 800x600. There was a slight improvement giving the FS 800x600 shots vs. 640x640, but you could use 640x480 shots to get the most on the drive.