In order to get rid of the "device not recognized" error you have to plug the saber in with it powered on.
However that only clears one hurdle, the next one is getting the software to recognize the board. I've tired everything, hub, uninstall and reinstall, unplug, turn off, replug, different cable. Nothing works, basically I just have to keep power cycling and plugging in/starting the app and hope it recognizes the board.
Very frustrating to buy the upgraded board and not be able to use it.
I have had success with the USB splitter, for some reason.