Comments about:

Longcat releases H3D plugin

bahhh...just Windows crap.....

Probably goes on Mac very quickly like AudioStage and others longcat Audio software, I mean.
D-cipher

ok, lets hope this.

From what i am seeing here in these pictures is that your input signal is going into the motu and you output signal is coming from you mac pro audio card
And this is where the problem is if you want to us the motu and the mac pro audio card together you have to GO to utility select audio midi setup and create a aggregate device(joint sound cards together to make one)
So create a new audio device with you motu interface and your mac pro audio card and give it a name then exit and reload preference
then go to preference and choose the device you just created for input and output remember the input and output depends and how you place the cards when you were creating the new device so the one at the top will show first.
I hope this helps
if you want i can send you a video in more details explanation

H3D for ProTools just released on Mac & Win!...