Unfortunately, Steinberg has implemented the feature in such a way that it can’t be used with third party libraries. They have “invented” a separation in “Directions” and “Attributes”. Directions are valid for all notes from the insert position on, until another direction is scored & Attributes belong to single notes.
The problem is that only one “Direction” attribute can be used at any one time! This is not how keyswitches are handled in any sample library I’ve seen. It’s very common to use multiple “Direction” keyswitches simultaneously. Until Steinberg removes this limitation, the feature is pretty useless. I’s just as useful as a MIDI track that can only record one note (monophonic) at a time!
This is a great shame, since it’s a brilliant concept. It could keep the MIDI editors much tidier and not cluttered up with not musical notes.