While true, the key switches are there in the MIDI import (which I’m assuming this is) so just creating the expression map won’t help. Studio One has a nice feature: create the map, apply it and then “Turn notes to key switches…” or something. I don’t believe Dorico has such a feature.
I don’t think it’s possible with an import like that. It becomes even more complicated because Ample has secondary key switches inside the range of the guitar. Separating those out would be next to impossible. Upper and lower notes outside of the guitar range should be easy in the key editor - that might get you pretty close (you then, of course, lose the articulations in playback).
I changed the instrument into Jazz guitar (in Setup mode) since I don’t have your VST.
Then in Key Editor you can easily select (with Marquee selection) and delete the very hight and very low notes (for the whole piece, here I show only the beginning):
You can then reapply your VST, using a custom Playback Template or manually (with the appropriate Expression Map, Playing techniques and so on…). I don’t have your VST so in my example I used the Dorico factory Jazz Guitar. You may need to reinsert the desired Playing techniques, etc…, but it is a clean and good starting point.
edit: after examining file a somewhat quick solution that preserves the articulations is to move all the keyswitch notes to one voice and the played notes to another one, edit > filter > voices > (choose voice), cut and paste to a new staff, and hide the staff in page view with Manual Staff Visibility.
basically I have to duplicate the stave , and delete there the KeySwitches for display and hide the original and use it only for playback, would there be any other better way ?