D F Tweedie
I'm just getting my 'head around' BIAB ... but I'm pretty sure this will do the trick.
There is a nice, free Midi program called 'Anvil Studio.' Download the regular, free program and install.
Open up the file you want to use.
Find your guitar track and note which one it is.
Delete all the other tracks using the functions in the program.
'Save as' with a new name ... maybe the name of the file with "guitar" appended at the end.
Open your new file in BIAB. There will now be a single midi file on the melody track. You can also move this file to the soloist track I believe.
You should now be able to access if with the guitar notation window either from the melodist or soloist tracks.
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