I have the modular hooked up to a mixer. 6 mono and 1 stereo from the modular into a Speck Electronics X.sum mixer.
http://www.speck.com/xsum/xsum.html
Rytm stereo out (using to record Rytm onboard fx) -> Speck X.sum
OTO Biscuit stereo out (der OTO mode) -> Speck X.Sum,
4 mono 1 stereo out from RME Fireface UFX+ -> Speck X.Sum,
Speck X.Sum A out -> OTO BIM -> OTO BAM -> RME Fireface UFX+
Speck X.Sum B out (pre-fader) -> Analog Heat -> RME Fireface UFX+
8 individual outs from Analog Rytm -> RME Fireface UFX+
This way i can record in any diffrent way, multitracking and return from RME Fireface UFX+ -> Speck X.Sum for adding fx.
Im quite satisfied with this setup at the moment and it works without any computer if needed. So if my computer would die on me i can still enjoy recording music directly to USB stick on the RME Fireface UFX+