I use BB Windows for live gigs, playing back my tracks on the sax and reading the lead sheet as it scrolls by.
There are just two things I would like to see improved:

1. It would be great to be able to enter courtesy accidentals anywhere, whether they're technically needed or not.

2. I have BB set to scroll ahead two bars (I've also tried one bar) when it reaches the end of a page (3 lines). When playing a set from the juke box, the scroll-ahead doesn't always work.
This has been the case with 3 different computers, and while talking to tech support one time, the tech support guy tried the same thing, and it happened on his computer, too.
For now, my workaround is to enter the note name of the first note on the next page under the staff at the last beat on the present page.

Those are about the only real issues I have with BB. I hope somebody can address them.

Thanks, guys (and gals)! BB is by far the greatest bang-for-the-buck in the entire market. If I could only have one music program, it would definitely be Band-in-a-Box!