My first experience with that library (and orchestral libraries in general).
Ran across a few problems:
When using CC11 to create a sudden volume change, the release sample of
what comes before will also be affected creating an unnatural decay.
I couldn't figure out how to turn the release samples off (if at all possible..?)
On fast cello runs, especially on chromatic ones, the release samples cause
a sort of harp like effect, where the notes keep ringing in an unnatural way.
I couldn't find an articulation that worked, and ended up altering the phrase.
I had 8 instances of Kompakt running in SONAR 3, and while I could play the piece flawlessly @ 1.5ms latency, I couldn't get a mixdown without errors, notes would be cut off here and there. I had to bounce each instance to audio and then bounce the audio.