Ed, did you plug in the 9-pin serial interface cable into a free serial port (COM port) as well? it is always required even if you use the game commander. The other end of the serial interface cable is a stereo jack. Just leave it alone. You could plug this into your own Tx with the proper adapter if you choose to use your Tx instead of the game commander later.

Additionally, pls ensure that there are no other programs running in the background. Cheers !