I'm late to the party here. I haven't plugged in hardware nor loaded drivers yet, but My blue vag 409.1 cable and Fiat adapter couldn't have worked as delivered due to an incomplete ground path. It appears that only the "K" and "L" line functions apply here, with IAW15 pins 9 and 10 passing through Fiat cable pins 3 and 1 to the OBDII connector pins 7 and 15 respectively. Additionally the blue cable needs 12Volts and ground via the red and the black alligator clips respectively, to OBDII pin 16 and pins 4/5. My problem was that the Fiat cable ground only goes to OBDII connector pin 5, while the blue adaptor cable ground circuit only went to OBDII connector pin 4. So the board in the blue cable couldn't be powered up and the K and L signal levels had no reference. My fix was to move the black wire inside the blue housing from pin 4, which went nowhere, to pin 5, which gets to IAW15 ground and battery return. So if if you have a problem with the blue cable, this might be worth checking.
Thanks for the good work you guys have done here.