@mediamogul Good idea on the directory thing. I may try that. From the sound of it online BlueMSX (which is libretro compatible) plays some of the carts. So maybe I'll try that first, and then switch over to Coolcv for other specific games that wont play.
100% agree that a pretty interface doesn't mean anything if the game runs like poo. It's just I've got so many of other systems running smoothly with overlays and fancy doodad's that the ones that don't drive me crazy in the back of my head. :)