SUCCESS!!!
Thank you to all that persevered with this thread. I had a crash course in multimeter usage and learned about bridge rectifiers.
Moved the jumper back to the original position on the DMD. Initially, all I had to do was remove the 5V wire and put the +12V wire in its place. I don't know why the pin repair guide said I needed to stuff around with changing jumpers?
Steevsee, Beaky, Mike, Blair and anyone else that helped, I owe you a beer!
Cheers!
Adam.