I might be missing something or this might be a bug? It works fine with the popover but when using the right sidebar I can’t seem to get a 1 beat pickup bar in 5/4 time. I’m using the latest Dorico Pro 6.
A 1/2 beat pickup works as expected:
But a 1 beat pickup results in 2 beats:
Thanks for your help.
The syntax in the popover is always x/y,z where z is the pickup value in the duration unit of y.
Double click the time signature – or select the time signature and press RETURN – and enter 5/4,1
Dorico – unlike Finale – is keyboard related. Please get used to it. It’s worth it 
The behavior of the panel does seem odd, but as @Vadian indicates, it works correctly in the popover.
