Several years ago, I sent my HC-1 into Ring to get upgraded to an HC-2, for a nominal fee. Ask Tim if that is still an option.
The LM-1's do have a very limited memory for sound files. I don't think any of the new Ultimate files will fit in along with bell,, horn and light and picture files. If you get an update from Tim on a LM-1 upgrade, please let us know. I've told him I am interested, but I don't want to keep bugging him.