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Well, you'll have a bit of a problem using the XDJ-RX for time-code as the decks don't have independent output via the soundcard, so you are unable to send that signal to the software. You could try and configure the MIDI but there are no official TSI files for Traktor and the XDJ-RX, nor is there the ability to send MIDI signal (for LED illumination or screen data) to the controller.
CDJs are your best bet for MIDI or HID mode (if they're any of the newer models with USB connectivity), no NI interface required.