Well, we needed to know that 0782 gave some sort of response. Trying all 256 EFCs, when you don't know if the protocol or device number is right doesn't sound too appealing. So at least some of your "screwing around" was absolutely neccessary.
I didn't know that the RCRP05B won't accept EFCs on the power key. But I checked over at hifi-remote.com (searched on RCRP05B and Power) and them's the facts. I tried it here, and by using a JP1 cable, it is possible to make the EFC assignment, but so far I don't know of any way to do it manually. One guy over there chose to put the power toggle on the dash key.
I assume that you know that the power key will accept a macro, but it only runs when in CBL mode. You can assign the DVD power to some key, and put that key in the Master Power macro, but it will only run if you've first chosen CBL mode. I don't why they did this, but it is apparently similar on other UEI remotes.
The EFC codes aren't the actual command numbers sent to the DVD. I used RemoteMaster (links at hifi-remote) and entered most of your discovered EFC values. Surprisingly, there is not much coherence to the actual command numbers. That's unusual. For example, here are the digit keys. OBC is the actual command number.
So I doubt that there is much hope of inferring the Exit EFC.
Did you find a EFC for ordinary Play?--I only saw Step Play mode.
Lots of remotes don't have a button dedicated to Open/Close--our Sony BluRay OEM doesn't have such a button. Some people put Open/Close on Stop-- press Setup, then Stop to open/close. It seeems to be easy to remember. The 994 instructions tell how to set that up.
