Congrats!! I personally use it like this
MIDI out from OT to - A4 - MnM - MD.
A4 Audio out OT, MnM L output to MD, MnM R output to A4. By doing this, I dont have to mess around with cables if I want to use either MD or MnM for further processing. As the inputs work monophonically on MD and A4 I dont mind having it setup like this. MD goes into the other stereo pair in the OT.
I use the OT midi sequencer to control other gear, especially MnM in poly mode 