>import McdUnits as McdUnitSystemSI Mass,Length,Time,Current,Temperature,Luminosity,Substance,Coding);
I have never tried to do this because it makes the Mathcad sheets completely non-portable, but that line implies you are trying to add a new dimension. I don't think you can do that. You can add a new unit, or a new quantity, but you cannot add a new base dimension.
Much like Fred said. Use the search and look up some help that Tom assisted me with. It had to do with Decibles. He showed me how to add the unit definition at the top of the sheet which I then collapsed and "hid". This made the sheet portable as anyone opening the sheet had the definition built-in.
Sounds like you're trying to alter the basic universe that mathcad starts in. Before xml coding the way you did this was to create a new template with your new unit defines in terms of the built-ins. You can put these definitions in an area at the top of the sheet, collapse the area and remove the icon and line so it "disappears." If you save that as a template, every time you open a new sheet your units will be there (but not shown) ready for use.
I haven' tried to do what you're describing for the same reason I don't script--I'm a coward. But the old way will still work in 14.
