I'm trying to import cad files into Revit details. I've issued the BASE command in ACAD, clicked on a line in the drawing to be imported, and then saved the file. I then use the Import CAD button in Revit, select Positioning: Manual - Base Point and click where I want it but I receive an error that none of the created elements are visible in the view. If I go to a 3-D view I see the imported cad drawing floating in space far from the insertion point, and in a different z-plane. What gives?