David,
So many questions! Let's try and pick them apart one by one.

First off the 15-1924 remote is completely different to all the other Radio Shack remotes. This one is a clone of the IBM/X10 remotes, so you can't use things like advanced codes on it, etc. Stick with your new 15-1994, you're gonna love it. Even though the button layout for your amp may not suit your taste, you can use key mover to move the buttons around until they suit you exactly.

Regarding the 15-1995 remote, although it looks similar to the 15-1994 on the outside, it's also completely different on the inside. The 15-1995 is a clone of the OFA Producer 8, whereas the 15-1994 is similar to the OFA Cinema 7. Also, I don't believe the 15-1995 uses it's RF feature to control X10 (I could be wrong as I haven't tested this feature), I think it also needs a converter box (IR543).

The 15-1994 can control X10 but does need an IR-->X10 converter box.

Regarding memory usage. There's actually three memory banks in the 15-1994, the first is used for advanced codes and macros, the second is for upgrade codes only, and the third is for learned commands. So, adding new device codes doesn't affect the two main memory banks at all, which is cool. In fact, I originally had to use several advanced codes to fix the button layout for my Samsung VCR, so in order to free up some memory, I created a new device code for it with the buttons layed out exactly how I want them.

As for the software, I will add it to the site at some point, but it's still very primitive. All it does is dump the memory and re-load it and it runs from a DOS prompt. We have started two new programs that you can use to decode the dump based on my discoveries of the format, and then reformat it again. These are also brand new programs and I've already found a bug in one of them, that's why I haven't put them on the site yet. If people ask me for them I have some idea of how many copies are out there in circulation.

NOTE: The Radio Shack web site and 800 number are both showing the 15-1994 as being out of stock, I don't know if this means that it has been discontinued or not, but I would recommend anyone that doens't have one yet, to rush down to your local RS store and grab one up while you still can. It's possible that there's a new and improved model around the corner, but will it be as hack-friendly, who knows????

Rob.