Okay, here goes ...
Starting with a completely blank project :-
1.) Add Omnisphere through either the Synth Rack or "Insert Soft Synths". When presented with the window I choose MIDI Source, Synth Track Folder and All Synth Audio Outs Stereo (later when you know how it works, you can try other combinations, e.g. simple instruments, mono, etc.).
SONAR now builds a Track Folder, 8 stereo audio tracks, assigned as Channels A to H, and ONE MIDI track assigned to NO channel.
2.) Clone 7 more MIDI tracks by selecting the one just created (should be track 9) and using "Tracks / Clone"
3.) Optional, but I do it ... Select all newly created MIDI tracks (10 to 16) and move to Omnisphere folder by right clicking on any selected track and using "Move to Folder" -> Omnisphere.
4.) Assign MIDI channels to the MIDI tracks (use Channels 1 to 8)
5.) Open Omnisphere, go to MULTI page. At left you'll see that all channels go to OUT A, so change channels 2 to 8 to route to OUT B, OUT C, OUT D etc. using the dropdown.
6.) Select you patches (I do this in Omnisphere, as I'm not sure what happens if you choose them in SONAR. Theoretically it should also work that way).
7.) Record your MIDI tracks, one by one or collectively, or feed the cat ... whatever ...
8.) Play back and you'll see in the CONSOLE that each output has its' own MIDI and Audio channel.
That's it ... easy as giving the cat another goldfish !! I hope this is what you asked
