Hi,

as the reverb is the only real dissapointment for me with the Fireface UFX and the reason I did not monitor itb so far and there are no plans to open TotalmixFX for VST I have found my own way of using my favourite Reverb (VVV) as monitorreverb from within Totalmix.

Maybe you find it useful, too. (Windows).

Make a hardware connection between an output and input on the fireface. I use the AES as I don't use it otherwise.
Put an instance of Herman Seib's VST-Host in your autostartfolder and set the inputs and outputs to the used hardware in-and outputs and load your reverb VST.

In the hardware output of the used channel (bottom row) turn the effect return to the max and enable the Delay. Set the delaytime and feedback to 0 to use it as an aux send (thanks for that possibility RME) and the spread to 0 as well.

Now you can use the AES Fader in the softwareplayback row to feed the reverb to the desired outputs instead of the effect returns.

Now you can use your favourite reverb plug in just as the Totalmix internal reverb.
My VST host starts minimalized, so that I never see it. It just runs in the background and calculates the reverb.