Apple Logic Pro /LogicExpress Discussion

Hello,

Does anyone out there use MOTU Symphonic Instrument with Logic?  I do,
and it does work, but not in the way that I thought.  I can designate
SI as an external instrument for a track, and it works fine.  However,
I see that SI itself is capable of several voices simultaneously with
each iteration of the instrument -- but I am only ever using the first
possible voice in each track.  I have been calling new iterations of
SI for each track.

My question is: is there a better way to use SI in Logic?  What's ideal?

Thanks
Jim