Hi Ben,
I suspect that the recent OSX update (10.7.5) may have introduced a bluetooth stack error…similar to that introduced with the new Mountain Lion OSX (10.8.x). Hence, until the amazing software gurus can iron out the bluetooth issues, you may want to invest in the Smoothboard for Mac software (http://www.smoothboard.org/mac/download/) as a work around.
Hope this helps,
Ken W. - Nipissing University