yeah, still working on that, didn't want to mention it so not to derail the thread but, yeah, this summer. that feature has been swallowed up by a larger project, but thats going full steam ahead. that whole thing started from originally thinking about doing the simple adapter pcb. and it grew into a beast, you all will love it.
hmm. yeah, DMG-NES (just simply that) wouldn't be too hard, i'll get all my notes out on that relevant stuff and do something super simple in the meantime. originally the plan was DMG to nes/snes, but it grew, but doing just dmg-nes would be so much easier anyways (at least not having to add functions for the extra buttons)
so, yeah. but, OP, in short its not a quick 1:1 connection, you need to translate one to the other. there is no quick fix currently that i'm aware of.