[FrankJ]

Assuming you are using the adapter that comes is the kit of parts....
It need to be wired per the getting started guide. Just plugging the wires in logical holes will not work. Do not forget the resistor although that has nothing to do with the RS-232 side of things. Make sure you are using a straight wired 6 wire cable. A lot of the premade canbus cables are 4 wire which will not work for the cable to the computer or CRIO. Try Ohming out the cable be sure everything is wired right.

If you only have one com port on your computer, the BCD will only have that for an option.

If you are running win7 64 bit, try running in XP mode. It may not run in 64 bit.

The solid yellow LED means the Jag is getting a 0 speed command. A logical consequence of everything connected correctly.