Some new user DM42/HP42s programming questions

[Androsynth]

So, in between the madness of moving, I've been fooling around with the new DM42. My main interest in getting this was for programming, and I plan on writing some programs for it that fill niches no one has addressed yet. There are also mountains of old HP42s software that could be tweaked to take advantage of that glorious screen on the DM42. All that sounds intriguing, so, a few questions:

1. Graphics: what are the main techniques for displaying text/graphics on a DM42? I saw the thread where a matrix is used to allow printing text. Graphics seem to be using a bunch of related commands centered around the 'alpha register', but the alternate manual doesn't go into much detail about any of this. Any tips or links? I'm assuming it works like the old Sharp BASIC computers where each byte turns off specific bits in a row? I'll eventually get the CDs with the original manuals, but moving prevents that at the moment.

2. Is there a detailed command reference for each of the RPN commands available to program with? I could probably get by on just that if such a thing exists.

3. Any fundamental differences (outside screen size) for converting between HP42 and DM42?

4. Lastly, what is the command to set the different graphics modes on the DM42? I'm probably just blind and missed it.

Thanks!