The multiriffs you can generate the entire track or selected bars,
but it will add a one bar pad (empty audio) on each end, this will cause problems, they need an option to add the empty bars from -1 to one bar after the end bar of the riff, this way you just drag it in, no messing around to line it up.
This is how you can do it in Biab when you create multiriffs in it.