I am trying to build a family composed of HSS members for diagonal kickbracing at parapets. In the past I have always used reference planes to control the geometry of families. However, now when I align and lock the top & bottom of the parapet post to the bounding reference planes and then try and move the top reference plane, Revit says "Constraints are not satisfied." Does Revit not allow you to lock the ends of structural framing members to reference planes? I really don't understand what the problem here is. I have tried using the "Generic Model" and "Structural Framing - Complex and Trusses" family templates. I get the same problem in both. Has anyone ever built a family using reference planes to set the lower/upper bounds on the height of a column? It seems that this shouldn't be a problem in Revit. What am I missing? Thank for your input!