Taking it slowly:
- Use the MixControl utility to route the S/PDIF input(s) into Core Audio channel(s) your DAW can recognize.
- Load your DAW and VC, in 3 out mode, make sure all 3 aux outs of the virus are presents and visible.
- Create track(s) (stripes) feeding the Core Audio channel(s) carrying S/PDIF audio you created earlier. You will need to arm and enable monitoring for them in order to hear them.
- Load 6 random sounds into 6 VC parts. Under the common tab set each one to a different output: USB1/2/3, out1/2/3.
- Create 6 MIDI tracks that send to the VC plugin each on a different channel, same channels as the parts you loaded the sound into.
- Arm and play each MIDI track separately, and watch the level meters on the audio tracks to see where the sound comes from.
Hope this helps.