On odd time styles, BB seems to load the '5/4' time into the 4/4 tempo; in other words 5 beats happen in the time span (in ms) that 4 beats would occur normally. It's a faux (fake) 5/4 time to me. You can only generate new tracks using a matching 5/4 style.

This is a big reason why I prefer Realband; it seems to use the real time signature and tempo much more accurately.
5/4 actually generates in 5/4 .. however then your BB '5/4' styles may become weird. You need to let RB handle the time sig change.

I prefer to generate a 5/4 time sig and have it line up with the tempo map. RB does this much better than BiaB.

I can generate a '4/4 style in RB' while using a 5/4 time sig (or 7/4 for that matter) and it makes sense. There are 5/7 beats per measure, and I can edit as expected, etc.

I do not work here, but the benefits are still awesome
Make your sound your own!