Some control over preferences for Weight and Dimension units is given within Maxsurf automation. The preferences only affect the units within Maxsurf. Units within the automation interface always work in metres and kilograms. These preferences are described in Preferences Object on page 25 and again on page 47 in the Units section.
There is also a preference for the surface precision. Changing the surface precision within Maxsurf (Surfaces | Precision | . . ) will change the number of stations used to calculate parameters of the hull. This can be seen by turning parametrics on, (Display | Net | Show Net). The surface precision determines the number of stations used to calculate the hydrostatics, which will affect the accuracy of the hydrostatic calculations.
The Precision property is described in detail in the Precision section on page 47.