Well, i finished wiring the Mendel this weekend. I only hooked up one of the stepper drivers and disconnected the extruder board just in case. Then I plugged in the USB cable and ..... Green Light! The main board LED lit up just fine. Since I was feeling foolishly overconfident I also plugged in the 12v source for the stepper and got a green light on that board as well. Unfortunately that is as far as I got.
The green light on the stepper board faded out over about 5 to 10 seconds. When I disconnect and reconnect the power I get the same reaction - first a bright LED which fades quickly to nothing. I have no idea what is happening there.
The Main board, on the other hand, is a different problem. There didn't seem to be any communication between it and my laptop so I went back and re-read a lot of the Techzone information. It turns out that the firmware loaded prior to shipping is for the Makerbot so i will have to load up the Reprap firmware before I can go any farther. Given my limited tech savvy that is harder than it sounds but I am working on it. I have the Arduino IDE and Sanguino extensions downloaded and tonight I will try to figure out how to get the firmware loaded.