If you mean the dimensions shown in the inspector, rulers and a few other places, millimeters are not an option. You can get inches, centimeters or points. To cycle through the options, you simple click one of the dimensions shown in the top of the Inspector's position tab.
Thanks but no its the custom page size at the bottom of the layout tab, if I click the points text it doesn't cycle through the options
Don't see a "layout tab" in FileMaker 14. Don't see a "layout tab" in your screen shot. There's a layout menu, but I find nothing that would open such a window at the bottom of the layout menu either.
What did you do to open that small dialog?
I found something PhilModJunk doesn't recognise I didn't think it possible :)
I clicked the layout icon highlighted and then Custom Size at the bottom I want to create a layout for some labels that are 9cm x 4xm