I've sent the right pitch bend data to the GPO kontakt player in Tracktion, by using 100:0 and 101:0 and then setting 6:12 and then setting 100:127 and 101:127, which sets the pitch bend range to default at 12 semitones (1 octave).
However, GPO does not seem to understand this ridiculously simple command. Rather it prefers to play up two or down two notes (1 sixth of an octave, 2 semitones). This is very strange. I would assume that this could be overcome by using the data entry CC #6 but sadly it appears not to work.
Whatever is causing this problem really needs to be addressed in short time. There are hundreds of thousands of MIDI compositions that would sound beautiful if only the pitch bend range could be set at 1 octave (12 semis). At the moment the midi files I am playing sound absolutely horrid, almost like the whole damn song is out of tune. These files have the CC#6 data already set at 12, and with the appropriate 100/101 being set to 0 before the CC#6 change and then being set back to 127 after the change.