If you do a drag n drop into Reaper it will snap it to scale or chord.
It will also create a scale or chord snap guide that you can easily see what notes are out.
You can then drag out of Reaper and import back to Biab.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
Reaper-Snap-Scale.png (26.4 KB, 40 downloads)
Reaper-Scale-Snap-Guide.png (27.3 KB, 40 downloads)