If you open the On-line Help window and visit a topic that contains a picture, and make sure that the LAST help topic you view does NOT have a picture, then when you quit FreeStyle you will crash.

The workaround is to be sure a picture in Help is visible when Quitting. Windows versions do not have the bug because they use a different on-line help system. MOTU's next FreeStyle 2.x Mac release will correct this behavior.