Other time signatures have been a long requested item, but have never eventuated.

I suspect the underlying code still only supports up to 4/4. While the styles 'sound' as 5/4, it is difficult to for me (as a classically trained musician) to read what is clearly a 4/4 time-signature notation and play it in 5/4.

And yes, mixing multiple time signatures could be challenging in BiaB. (Don't go near Dave Brubeck's: Blue Rondo à la Turk).

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