There are two MIDI standards that define Middle C, and they are one octave apart. Our virtual bass guitars have to adhere to the standard that Kontakt Player uses, which begins at C-2. Whereas some DAW's and other applications use the other standard, which begins at C-1.
What this means is that when importing MIDI from an application that uses the other MIDI standard, you will have to select the whole MIDI item, and transpose it up by 1 octave to compensate.
Also, if you are using our virtual bass guitars in a DAW that uses the other MIDI standard, then everything in that DAW's piano roll will correspond to one octave lower in Kontakt Player's piano roll. This is the case in Reaper for example, where C1 in its piano roll will trigger the C0 key in Kontakt Player.
Likewise, C-1 (the lowest key in Reaper's MIDI piano roll) will trigger the C-2 key in Kontakt Player, which corresponds to the Pick articulation.
Basically, it is just a numbering and naming difference between the two MIDI standards. You can still utilise all the features in our virtual bass guitars.
You can offset the piano roll display in Reaper so they are correct. Reaper Preferences> Media> Midi> Note Name Display Offset and I believe you would want to set it at -1 but you can try different numbers if it’s still off.