In the MicroScribe Utility Software (MUS) there is a configuration toggle for you to choose the units of measurement you wish to use, inches or millimeters, when collecting data with your MicroScribe arm.
When performing the SPAT (Single Point Articulation Test), there is also a toggle in the spreadsheet to choose the units. Whichever units you prefer, be sure to set the units in MUS and the units in the SPAT to the same type.