The part in the manual about only being able to learn to the four smart keys is an absolute LIE, so yes, you can learn to most of the other buttons, with a few exceptions - like Edmund mentioned, so give it a try.

If you don't have enough learning memory for the two strange devices that you want to control, and you really want to control them using the 15-2104 in addition to your MX500, I suggest you check out JP1. using JP1 you can create new codes for the 15-2104 which you can upload from your computer.

[Link: hifi-remote.com]

Rob
http://www.hifi-remote.com