Same here, really want to know what we can do to see what's inside this extension-less M file that's in there, if there's a rom or what. Because the dream would be to get this playing on a real system 18 (even if it'd likely be without music, since the music was reimplemented through old recordings they had), just for the sake of seeing it on actual hardware.
Then there's always MAME and FPGA's that would be interesting to see it on.
Of course I'd also love to play this on my candy cab, so there's that,
Really wished they did a Steam release, since then you could likely play it native res RGB on arcade machines using CRTEmudriver, much like how you can play games like Steel Assault, or Streets of Rage Remake.