2010 and following builds have seriously improved the user experience with BIAB.

But I have run across a stability issue that I believe started with the original issue of 2010. Several times now when attempting to save a BIAB song the app has shut down after the save button in the file dialog was hit. Usually it does not. Unfortunately, a save operation is often the last thing I do when going on to other things or shutting down the computer, so I might not even notice that the app was no longer up. I think the save operation executed successfully before the crash in at least one case. There is a possibility that there is a conflict between a file utility I use (Default Folder X 4.3.6) and BIAB. This utility enhances open and save file dialogs, but has been no problem with other applications. I'm currently running with the utility off to see if the problem recurs.

Unrelated: there is one basic area in BIAB that could stand some improvements, the chord window. It would be much nicer if single (or multiple) line scrolling were possible, both with the scroll arrows and the thumb, as is the case with word processors, text editors, etc. With only full page scrolls now it is difficult to work on a chord sheet longer than a page near the transition from page to page. Also, if one now resizes this window vertically, the line height currently scales to keep the count intact. 16 lines of 4 measures is fixed. It would also be an improvement when resizing vertically to keep the full line height and reduce the number of lines displayed. Just suggestions...

Snow Leopard 10.6.2
Mac Pro early 2009

2013/73
MacPro early 2009 2.66 GHz, 3GB
Mountain Lion 10.8.3
Ketron SD-2