I removed the LED took a bulb from an Atlas/Kato RS3 and tried it; no dice, so I guess the problem must be the board itself.
Since I need some additional items from MTL, hopefully they'll be able to supply me with a board as well...
Mark in Oregon
Mark, a light bulb? As I mentioned (few posts earlier): There likely is a current-limiting resistor on the circuit board for the factory-installed LED. If you replaced the LED with a regular bulb, then the chances are that it will not light up (because the bulb needs more current than an LED, and the resistor is limiting the current).
Hopefully MT will send you a replacement board - no more troubleshooting will be required.