I tried resetting the AMP screen and it would freeze every time I tried. It would clear the learned commands, but any label changes I had made remain. They just need to be re-learned from the original remote. Also the keys I chose to hide remain hidden. I read somewhere that you have to hit "DEL" and "AMP" up to 3 times to completely erase the "AMP" screen. This is not possible as the unit freezes upon the first press of "DEL" and "AMP".
I also tried deleting the left arrow key, and this can be done without a problem (as with any other key it seems). I thought maybe using a PRESET code might get things going, but I guess I cannot enter that now without being able to delete the component first.
I hate the thought of resetting the whole 3100. My other option is to program the right arrow key on one of the label keys, seems a little silly with all the rest working down there, but perhaps it is time well "saved". This does work as I have already tried, but it would be great if that final key could be rectified somehow...