hey guys,
thanks alot for the additional bug reports.
Just like RobBr assumed, the key-editor scales itself to the range of the assigned instrument.
The Am Kits come with 16 samples, whereas all other Drum Kits contain 6 octaves of samples.
So once you change the instrument of your MIDI Track from one with more sample-presets to sth containing less samples, the previoulsy recorded notes might be out of the new range and are not being displayed.
Unfortunately they are truly being played back as samples bordering the new range, shifted in pitch.
To avoid this buggy behavior I suggest using one MIDI-track for each instrument.
The 2nd issue concerning the AM Kit piano-roll scale and its hidden note on either side is indeed really annoying.
We are aware of these bugs and will fix them as soon as possible.
Kind regards
Ludwig