Bizarre Goings On

I open a VST track in Notion, choose Vienna Instruments Pro (not a Notion Preset). I then assign one of VSL's Chord Presets. I place the notes, enter the appropriate keyswitch notes setting them earlier than the playing notes and ensure that the corresponding matrix cells are loaded.
It plays perfectly several times, then save it. Then it doesn't play at all. I reload it. Same silence.
I export it as a midi file and load it into Logic and reproduce the instrument. It doesn't play. There are several keyswitch notes other than the ones I entered that Notion has apparently exported. I remove these. The file plays beautifully.
Back in Notion I find that if I copy a couple of notes and try and paste them into a new track they are not copied over except that occasionally these notes will now play on the problem track. Once. Change the page view. A couple of notes will play once.
I try to delete notes from the problem track. They don't delete.
I try the same thing with a simpler VST/Vienna instrument (the chord presets require 3 keyswitch notes) and it works fine but on midi export it shows the same three incessant keyswitches introduced by Notion (D-1/F-1/C9) but these don't seem to effect the output.
It seems that by introducing these keyswitches, Notion is confusing a complex instrument (and itself). Can anyone think of a way to avoid these irrelevant keyswitches?
It plays perfectly several times, then save it. Then it doesn't play at all. I reload it. Same silence.
I export it as a midi file and load it into Logic and reproduce the instrument. It doesn't play. There are several keyswitch notes other than the ones I entered that Notion has apparently exported. I remove these. The file plays beautifully.
Back in Notion I find that if I copy a couple of notes and try and paste them into a new track they are not copied over except that occasionally these notes will now play on the problem track. Once. Change the page view. A couple of notes will play once.
I try to delete notes from the problem track. They don't delete.
I try the same thing with a simpler VST/Vienna instrument (the chord presets require 3 keyswitch notes) and it works fine but on midi export it shows the same three incessant keyswitches introduced by Notion (D-1/F-1/C9) but these don't seem to effect the output.
It seems that by introducing these keyswitches, Notion is confusing a complex instrument (and itself). Can anyone think of a way to avoid these irrelevant keyswitches?