Thanks Circular,
I can try some different setting, but am not really sure what I am doing. My options should be standard, Level 1 debugger optimization, no special linking options (GDB, Automatic, line numbers).
I will probably wait for the next version, and see if others run into similar issues on OS X.
By the way, many, many thanks for your work on BGRABitmap. It is extraordinarily useful to me.
Cheers,
Frederick