A scene file can be found here.

 

Depth Mask

 

Object Position (n) Dust Mask

In Maya, you cannot connect a single out color (Out G) to an Input. A workaround is to use an RGBAtoFloat (mode G) shader to convert it.

 

Object Position (P) Mask

In Maya, you cannot connect a single out color (Out G) to an Input. A workaround is to use an RGBAtoFloat (mode G) shader to convert it.