Controller not working with Tatsujin Oh

[RetroRepair]

Hey guys

So I now have an FM Towns II and have modified a Megadrive controller to work with it and it seems every game works great with it.. except Tatsujin Oh.

I can press button 1 or 2 and it will take me to the menu screen but when I'm there I can't press anything! Really odd since the Megadrive pad is (as far as I can tell) technically the same as the regular FM Towns controllers. Only thing is I've tied select to 5v in the controller as the FM Towns didn't seem to be making use of it (I don't think they do).

Any ideas what's up here? I'd be great if someone could open their controller and take some pics so I could get an idea what's wrong.

[RetroRepair]

Well I figured it out, it seems it was the one game which didn't like the select line tied to 5v. I guess for this system you just need to disconnect it completely. Works great now