Can you tell us a bit more about your setup? It would be particularly useful to know what your signal chain is, what audio interface you are using, and how you're currently trying to use the TimeFactor.
In that case, you should be able to just put the TimeFactor in one of the aux send/returns on the NI Pro 2 or the A&H Xone, depending on how you have Ableton configured and which device you want controlling the TimeFactor's levels. To synchronize your TimeFactor with Ableton, just connect a MIDI cable from the MIDI Out of the NI Pro 2 to the MIDI In on the Timefactor.