Enables you to turn camera motion blur on or off. 'Use Global Settings' will use the value set in the motion blur tab from the MtoA global render settings. This option can be useful when there are multiple cameras in a scene that may or may not require motion blur. "Use Global Shutter" (enabled by default) signifies that the camera should use the values from the Render Settings, in the motion blur tab. When you want to set a specific shutter in the camera, you can disable "Use Global Shutter" and then it will be taken into account.
The shutter range of the camera can be defined by changing the shutter_start and shutter_end parameters. The value range should use the same time reference as the motion times. The default shutter_start of 0 and shutter_end of 1 means a full camera shutter range equivalent to the default motion blur range. A smaller range (0.0-0.5) will decrease the effective shutter aperture time and only show the first half of the motion.