Problem with creating a cross section of an imported 3D CAD (STL)

Dear all, I have a 3D CAD imported geometry in Comsol 5.3 a , I want to create the cross section of this geometry in 2D. I follow the standard instructions, starting with creating a workplan in 3D and later add an other 2D component and generate the cross section from the work plan. And this always gives me an error message “Not supported on virtual operations”. However, this works for all the 3D models created within COMSOl. Does someone knows the reason of this problem or another way to get the cross section of a 3D imported geometry?

Thank you