@Cellcon Hi, Ive been on this forum for years, in the English section, and my PERSONAL OPINION, is that this forum is literally dead compared to the french one.
However, there is a lot more support on the Discord channel, and, if needed, so what ive done - bring up the google translate english to french, type in yer query, and put it in the French section if you get no response in the english one, then obv do a french to english back to read the response.

Ive used Retropie, Recalbox, Retrobat (which I still use on my PC) and Batocera, and, if you think Recalbox can be hard going..... Its easily the easiest to use, plug and play setup Ive ever used.
Is it perfect ?
God no, but, honestly, Ive tried them allexcept Lakka, which, rightly or wrongly, didnt even look worth the bother for my needs.

Oh PS

The md5 is a red herring - just get the correct rom set and your fine 👍