We are currently touring with the SL32R and we are using rear fills for fx and synths.
Our usual venues are 500-1500 seat theatres, where some of them already have 7.1 systems setup for live use.
Those who don't we ask they setup a Rear LR spread out in a few zones depending on the size of the venue, if there are balconies etc.
So, at the moment i'm just sending fx and what i want back there to a LR mix bus prefader.
And it works out really well..
But i can't see why Presonus couldn't add a 7.1 bus and a surround panner in the UC gui.
It shouldn't take up more dsp than routing 1ch to 8 monitors...
Motorlyd, Dreamers Circus' FOH.