I honestly have to say that I am not an expert of the HD500 at all, I barely know about all the possible options, I only the the very basic functions.
My rhythm guitars are basically two tones panned L80/R80 IIRC: one is a Recto model (treadplate) and the other is the Fireball model, both are boosted with a tubescreamer model. And there is a gate, that's all.
I used the default cabs an mics I think. Really not much tweaking there, I thought the amp models sound great from the get go, I just turned the amp knobs a little and was happy with the results. Throughout doing some testmixes for my EP I experimented with different amounts of gain and that was very important. At first I think I had too much gain, then I tried with much less and later I added some more gain as a compromise.
But like I said, I am really no expert on the HD500, like if I had to try to get the tone of some famous albums or so, I would have no clue as how to do that.
Check out MeAmBobbo's HD500 tutorials, he is also on this forum, he knows everything about this unit and has made so many awesome tones, and is a very cool guy!
I have not uploaded my patches anywhere, but mail me if you are interested and I can send them to you.