I've gotten into Bezels for my retro gaming recently, especially in MAME. I like how they give an arcade cabinet feel to the games and hide the black bits on the sides when you run old arcade games in the 4:3 screen ratio on HD TVs (which are 16:9) to try to preserve the aspect ratio these retro games were originally made for. As my MUGEN focuses on Marvel vs Capcom CPS2 style games made for the 4:3 ratio, I was trying to figure out how to make Bezels work for MUGEN (and DEMUL 0.7).
There's not a ton specifically on how to do this for MUGEN (or maybe my google skills suck), though I did find stuff for DEMUL, so I thought I'd post here that, after a bit of effort on my part since I am new to RocketLauncher, I figured out how to make it work. Here are some screenshots of what it looks like. The Bezel is an edit of a Marvel Super Heroes MAME Bezel created by Derek Moore. The scanlines are through Reshade and my internal MUGEN resolution is set to 320 x 240, which is the resolution of these old Marvel vs. Capcom CPS2 games (which means I can't show too many characters on screen in the select screen so most are hidden). And the Screenpack motif, characters and stage here are from ScruffyDragon (as was the tip on the 320 x240).
Not sure if anyone else is interested in trying to do this. If there's interest I can try to share some tips/instructions. RocketLauncher has some neat features that connect to FrontEnds like Launchbox (which I'm not yet using) but is not super intuitive if you're not familiar with that sort of thing (and I was/am not).
April Fools