FYI, the membrane pad is bad and that is why you cannot turn it off... this was very common with DM4's.
Also, the DM4 and 5's only had one firing mode, which was semi-auto. There is no ramp/3shot/full auto modes on the stock board.
The 187 plug is just a continous flow plug which replaces the On/Off flowplug that caused leaks on occasion.
So you might want to edit your listing and have it note that the gun is fine and all it needs is one of these
You're not getting offers because people are scared that the board is bad, when really the only thing is needs is a 5$ part and the gun should work flawlessly.