AT/Note Expression Parameter range controls with Kontakt/Spitfire


I’m working on a film score mock-up with new Spitfire libraries. I’ve successfully mapped the aftertouch of my MIDI controller to the vibrato of my solo violin instrument (Kontakt) as I usually do. This is what I’m used to play with. In the new version of this library, however, setting the vibrato value to 0 triggers a tremolo, so that if I play a note without aftertouch it doesn’t sound right. To work around this, I’m trying to set the minimum AT value to 10 or so, using the parameter range controls in the note expression tab of the inspector. They seem to be greyed out.

I’ve been looking the whole morning to find what I’m missing, without any success. Is anybody familiar with this kind of situation?