I am having to draw over PDF plans to create copies. I've set the PDF dwg as a trace reference so that I can draw over the top of them using the Archicad wall, door, window, tools. But I can only use some 2D tools such as lines and circles. If I try to trace over a 300 thick wall on the trace reference, with a new 300 thick wall, it doesn't work. That can't be right, surely because it is called a trace tool. What am I doing wrong?