RK 1107 Challenger

I have been checking out a couple loco's I picked up over the last 18 months, checking battery condition, corrosion, function, etc.  I have this MTH UP Challenger and in the instructions it tells you how to install the Protosound board on top of the direction control.  It tells you to pull this jumper and that jumper, and remove the wires for the reverse lockout...but, the board that is in it is nothing like the one in the drawing, and only has 4 pins, two on each side that plug into the direction control, plus a supercap instead of a battery.  Is the board labelled 'OSI' an after market board?   In my testing, I noted that the reverse lockout switch was in 'ON', and assuming this meant it would lock out reverse, I put it to 'OFF.  Wrongo big time.  Glad I did not smoke something as the 4 big diodes on the direction board got hot as fire, and only the rear engine on the Challenger ran.  When I put reverse lockout to 'ON', both engines ran plus bell, whistle and direction functioned as normal.  I have no info on the OSI board, and it must warn you to leave the reverse lockout on.  Any thought on the sound board plugged into this unit?  Thanks.