I finally received all the pieces for my PC Engine set up recently but I'm having a weird issue with my controller. It works fine for Neutopia but doesn't work at all for MAJIN EIYUDEN WATARU. The controller is what would have came with the original PC Engine originally so I'm not sure how it could have caused any issues. Not sure how it could be the port if one game works fine but not the other. Thank you.
if you are using an everdrive, could be a bad dump of the game. The game you just mentioned is the JP version of Keith Courage, and I have speedrun both versions on my pc engine duo/everdrive setup with no issues. Also, check discord