Read the MultiRiffs in Biab section below first if you are not familiar with this.
This is an update on how to create up a realtrack freezing sections that you want to keep and regenerating other sections, using the method below, you will be creating the track you need using up to 7 different sections using the F5 "Mute" or "Back to normal", so you keep the parts you like by setting the start of the section to default "......", the sections you don't want set the start of the section to "Mute" then "Back to normal if there's another section you want to keep.
The Muted sections will be generated on the other tracks, when done all the tracks will be merged to one track just how you want it or as near as can be.
I hope by Dec 2018 it won't be needed and this function will be implemented in BB19 ! but still those with older versions will find it helpful.


Generate and solo the first section in track 1 to your liking then mute it with F5 where the good ends and Freeze the track.
Solo Track 2 (and Audio) Un-mute F5 at that bar, Generate the next section to your liking then mute it with F5 where the good ends and Freeze the track.
Solo Track 3 (and Audio) Un-mute F5 at that bar, Generate the next section to your liking then mute it with F5 where the good ends and Freeze the track.
Solo Track 4 (and Audio) Un-mute F5 at that bar......

Now mute the Audio Track and Drag Render the master to get your RealTrack.

Further..
You mute the track where a riff ends then generate the next track to play from there this will work the same way that BB generates a whole track.
If track 1 plays good until bar 19 you F5 mute @ 19 and freeze it
now you can leave track 1 soloed (and the Audio track) now solo track 2 as well,
track 2 will be F5 mute @ 1 so now we F5 back to normal @ 19
hit play generate until we get it to flow and fit from track 1 bar 18 to track 2 bar 19 and on until a good section of playing ends and a bad bit starts, then mute, freeze, track 3 F5 back to normal... and so on.
Track 1 maybe give you good playing in the first and last chorus but the middle don't fit so you just generate the middle on track 2.


Setup 2 Instances of Biab (if needed)
IN Options > Preferences > Allow Multiple Instances of Band In A Box to be running..

MultiRiffs in Biab
1. You have your song made up in Biab but would like to get the soloist to play a suitable riff at certain bars.

2. Mute the soloist track, Save my song.SGU

3. File > Save Special > WAV/AIFF .

4. Save song As my song - multiriff.SGU

5. File > Import Audio > choose the wav/aiff file you just save, or rename the wav/aiff to the same name as my song - multiriff.SGU my song - multiriff.wav and reopen the song and the file will load into the audio track.

6. Edit > Song Form > Unfold

7. Select the first track and select the RealTrack you want to Multiriff in the RealTrack picker.

8. In the top left of the picker select the next track and set it to the same RT and so on until all 7 are the same RT.

9. Hit F5 on Bar 1 and set each track to mute except the Audio track.

10. Hit F5 on Bar 9 set each track to Back to Normal except the Audio track.

11. Hit F5 on Bar 13 set each track to Mute except the Audio track.

12. Generate all with >+

13. In the mixer right click on the Audio track solo button and right click the solo button on track 1 then 2 then 3 etc..
to preview each Multiriff with the other instrument in the Audio track.

14. When you find the riff that fits highlight the bars and export via DROP and drag to the same bar number in your DAW or don't highlight to export the whole track.