Problem

Dimension Style Terminator settings are grayed out in dwg workmode--Dimension Style Terminator settings are grayed out in dwg work mode.

Solution

Because AutoCAD always has terminators automatically oriented and it does not have fixed options like MicroStation. For example, if you set it to inside, MicroStation puts terminators inside, always. But you cannot do the same in AutoCAD, which may put terminators inside or outside, depending on fit options.

In XM, fit options have been added such that when you are in Automatic
mode, fit options will work exactly as they do in AutoCAD.