When opening rhino and a new window/workspace it always opens it with centimeters instead of millimeters (which is the common and necessary thing to do when designing most things).
In the options menu files>template files… change the default template to the, either large of small, object millimeters template. This will, when starting rhino, open the default template in milimeters.
Also, units can be changed in the unit section of the Document Properties page. Click on Properties under File, or type the DocumentProperties command, and then select Units.
I managed to change it. Thank you!!! To the Rhino developers. It would be good to have a visual element suggesting to change the default template. Maybe like the blue dot in layer to let you know where you work in. To do a secondary click on the template you want to make default doesnt seem to be a natural move in this type of window or even in Mac…or maybe its just me…but i left it now for so long when it automatically changed with an update because i could not find it myself.