Fireface should be fine with PT. RME is known for having the best drivers of any
(assuming a compatible FW card or chip, TI being preferred and VIA often being a show-stopper). The Tascam has a HUI mode, does it not? It should just be a simple setup to make it work(get the unit to enter HUI mode, and enable it correctly under the Peripherals menu in Pro Tools). I bet a search of youtube would turn up a few tutorials on getting the Tascam working with Pro Tools(and the setup details will be essentially identical for any version of Pro Tools)