I've been hard at work on the Ren'Py port of NLT Media's Lust Epidemic and thought I'd give you an update .
If you've played NLT's games, you'll know they have a lot of involvement from the RPGM sprites during conversation sequences. Here's a scene from the introduction of Lust Epidemic, where 8 characters are present:

If I just show the rendered parts in Ren'Py with a map background -like in the Christmas exclusive download I posted - you don't see who is present:

What I'm now doing is tracking which RPGM sprites should be onscreen, and added them as background image renders of the participants, faded out in a crowd-like shape:
It works pretty well, I think.
The problem in porting NLT's games is that these scenes are very dynamic!
There's lots of characters coming and going, so I am having to add "animation" for when the RPGM sprites appear and leave.
The "animation" is mostly just the static renders sliding in and out of the scene, so it looks a bit poor (think Healslut by Davie Zwei if you know that), but it's probably the best I can do, unless somehow I get supplied with remastered walking animations for all characters in all clothing (and no clothing!) combinations.
I'm about halfway through the opening part of the game in porting the scenes, and looking forward to giving you a teaser download soon once the whole first section of the game is reworked!
Mike.