TomTom,
I don't mean to avoid your question, but I've been randomly making "on the fly" adjustments and I can't pin point exactly what I've done except for - keyboard velocity, effects sends, EQ levels etc. A good way to get the best effects settings is to start with an OTS setting - then write it into a registration.
The growl sax was not sustaining the way a real sax would. (I'm a wind player, and somewhat fussy) There was an unnatural decay in the original setting. It might have been the effects - maybe it was gated or something like that. If I find any "sure fire" methods or workarounds, I'll post them too, but for now - you have to make the adjustments that suit YOUR own ears. Donny loved the growl sax in his - I needed a different sound for me. It was more in the playability than the tone, itself.
Chocolate & Vanilla, for sure!