I received my Instrument 1 yesterday and I'm pretty happy with it so far.
In playing around with it I've found I can hammer on and pull off from fret to fret, or hammer on from open to fret, depending on method and sensitivity, but I can't pull off from fret to open--the open note won't sound.
|--2-p-0-| just sounds like |--2--[silence]-|
Is there a setting somewhere to allow for open strings to trigger after pull-off from fret?
I'd guess not. Generally on a string instrument there's not much left of the open after a hammer-on anyhow, so any accurate programming would have to kick back in afterwards with less velocity.
If you don't need the bending of slide and can live with subdued opens present beneath your hammer-ons, your best bet might simply be an after-touch valve style grid.