I'm having some trouble with expanding instruments (a great feature btw, it's so fast and easy):
For example, I have an instrument track with Superior Drummer with the channel name Drums. I change it to multichannel in SD, then expand it Studio One into 6 channels (kick, snare top, snare bottom, hi hat, toms and overhead). I change the first channel to Kick. Now the main instrument channel is called Kick, instead of Drums.
There are occasions when it does work like I expect it to work, so the right order seems important. But I haven't figured out which order yet.