Hi Pete, I use my old MRC power pack. It has a volt and amp meter so I can see trouble early on. I test lights at 3 volts if I do not see resistors in line to those lights. If resistors increase to 5 volts. Then switch polarity, if they stay on it is a bulb. If too dim increase voltage to 14 or 18V. Did you know that RailPro can reduce the bulb voltage if you think is it too bright!! Pretty cool.
I am at a show this weekend but will send you lighting procedures on Monday.