You can lock the A and B parameters by hiding them. Open the object, go to the parameters and under Display cross them out. This should stop the object resizing.
I make 2d objects with hotspots by just pasting the linework and fills into the 2d symbol window. Editing them is just as fast as editing a simple group.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
Windows 10 Pro
Adobe Design Premium CS5