2104 should be supported, but DCS2 in general is in an unknown non-working state in M1. Part of the rationale of M1 2.0 will be using completely unmodified MAME components, which should in turn make it a lot easier to get things like that to work. But I'm not sure when that's happening yet. I want to make sure MAME's settled down first, and OG's been interested in redoing how sound works in MAME for a while so waiting until that happens would probably be a good idea smile