dga,

Yes, that's normal. Whenever there's a part marker, BiaB 2016 for Mac treats it as a "paragraph marker" and starts a new line. If you don't want that behaviour, you can turn it off for a single song (Song Settings button), or all songs (Display Options). That feature has been around for a long time on the Windows version, and is popular - it makes a chord sheet more readable.

Think of a song with a 3 bar intro, and then 4 sections of 8 bars each.
Without this feature, none of the sections following the intro would start on a new line.
With the feature, they all start on a new line, and its easy to see that they are 8 bar sections, and they are divided by a thin grey line etc.

btw, you can change these settings at any time - during creation of the song or before or after.

Have Fun!
Peter Gannon
PG Music Inc.