This is a guide from a question in the UserTrack forum:

Full screen Export BB Chord Track



Full screen Import BB Chords to RapidComposer



That's where RapidComposer make it easy, you can enter any tab or drag a midi bass pattern from a midi file into RapidComposer convert it to Relative form, Save it to the custom phrases library.
Open a UserTrack Template in Biab, in Prefs set Chord Output, save as midi,
in RapidComposer Import the midi file and select the BB Chord Output track.
This will give you the same UserTrack Chord track in RapidComposer.
Now just insert a new track load your Virtual Bass vst,
now just drag the save Reggae Bass phrases from your custom library into the new track and they will snap to chord/scale.
Now save the track to wav and put it in the usertrack folder along with the SGU with same progression and tempo.
You can then change the Key in RapidComposer and save as wav along with the SGU you just change the Key of in Biab to match.
Now you will have a Bob Marley Bass UserTrack in a lot of different Keys, you can save it in 12 keys if you like and in the F5 > UserTracks Development window you can set what part gets played where, if you do that with the first key template it will have the same settings in the other keys, so if you start in A, set the settings in the SGU in Biab then when you change the key of the template it will keep the UserTrack Development settings for each key SGU.

Bass, Acoustic, Reggae Sheriff Ev90 A.wav
Bass, Acoustic, Reggae Sheriff Ev90 A.SGU
Bass, Acoustic, Reggae Sheriff Ev90 Bb.WAV
Bass, Acoustic, Reggae Sheriff Ev90 Bb.SGU
Bass, Acoustic, Reggae Sheriff Ev90 B.WAV
Bass, Acoustic, Reggae Sheriff Ev90 B.SGU
Bass, Acoustic, Reggae Sheriff Ev90 C.WAV
Bass, Acoustic, Reggae Sheriff Ev90 C.SGU
Bass, Acoustic, Reggae Sheriff Ev90 C#.WAV
Bass, Acoustic, Reggae Sheriff Ev90 C#.SGU
Bass, Acoustic, Reggae Sheriff Ev90 ......

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