Has anyone ever tried this: ( VW 2017 ) - open a sheet layher - go to resource manager - right click on a symbol, edit 3D component   => move 3D and other 3D operations do not work as long as the "underlaying" layer is not a design layer. I'm not shure, but I think previevious versions did not have this behaviour. Opening a symbol in 3D edit mode should work in 3D edit mode, independant on what type of layer was previously opened. Bug or feature... ?