Try loading the correct PS32 steam chain files, a couple of power cycles later and you may find all is well.
Another point. You MUST make sure the two boards are firmly seated. There is a VERY SMALL pin engagement between the boards, and it takes very little for them not to make contact. IMO, this was a lousy connector selection by MTH, there are lots of more reliable board-to-board connectors that could have been used.