When I wanted to add the latest MAME and all the game ROMs to my build of CoinOps Next 2, I made a new folder in “collections” and a new separate MAME folder in “emulators”. That way I have the original curated collection from the original that will still have the ROM names from the version of MAME they used. I just called my addition “Arcade 2” in “collections” and the MAME version number in “emulators” and scraped all new media files for video and logos with “Skraper” (https://www.skraper.net/). Marquees came from https://www.progettosnaps.net which includes almost 4000 games

After eliminating all the non-video games from the ROM set, I have over 5000 working games, most with icons and videos.

MAME version updates often change the ROM names, so ROM names and media need to be updated for every MAME version. Use “Clrmamepro” for this, available here: https://mamedev.emulab.it/clrmamepro/

Be SURE to have a backup of you ROMs the first time you use this!!