Question about: "I can remove all the walls and elements except the 1 wall including windows etc., export and import it while rotating to put it on the ground. Then i can add all the measures needed."

I am stuck in the importing step. How do I import the obj file? If I import it as a furniture, it ...

Reporting failure on arch linux:

sweethome3d
com.jogamp.opengl.GLException: J3D-Renderer-2: Error making temp context(1) current: display 0x7f76241f8090, context 0x7f762445dc08, drawable X11OnscreenGLXDrawable[Realized true,
Factory jogamp.opengl.x11.glx.X11GLXDrawableFactory@2650fdf5,
Handle ...