I've dimensioned the distance between two parallel lines. One line is (I think) unconstrained by other relationships and one is connected to other geometry. When I change the value of the dimension, the connected line moves, no matter how I attempt to tie down that line with relationships, constraints, etc. I tried playing with this with a couple of free lines elsewhere and I had no control over which line would move. Is there a way to specify which element is to move when a driving dimension is changed?