What version of Mastercam are you running? In each operation they have what are called misc integers and reals that have switches. In there you will want to look for the place listing this follow what it says to input for activate the option. Depending on your version you might find an something on the tech exchange at the official Mastercam website. Without a Z2G with your post and everything else not much more I can think of to assist you further.

The system likes Metric, it is the default in the file header. If you build the machine in inch, after you save it, open the XML file in an editor and make sure that the header says inch or it will scale it when you go to use it. Example: <?xml version="1.0" encoding="UTF-8" ?> <machine_definition> <machine_data name="Fanuc_Robodrill" version="1.8" units="metric" controller=""> Change it to the following: <?xml version="1.0" encoding="UTF-8" ?> <machine_definition> <machine_data name="Fanuc_Robodrill" version="1.8" units="inch" controller="">