Just create whatever you want to use, you just need enough chords repeated so Biab don't over transpose chords to fit to another, so if you only have 1 C chord it will over transpose others to try and give variations.
You can create some 4 bar endings with the first bar normal playing then strum and ring out on the 2nd bar, these are sett as Ending in the F5 > UserTracks Development.
Because you can regenerate and change UserTracks now at any bar as well as Edit Riff function you can get them to play Holds, Push or Shot but you need an option for this so if you want to manually do this the UserTrack will play where a Hold is allowing you to change the UserTrack to the Hold UserTrack that belongs with it. The Holds can also be used for a Push or a Shot as you can easily adjust with the Edit Riff function.

Use "Don't start a new riff on this bar" to set 2-4, 6-8,10-12 etc.. so it will only play from start of Hold.
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