If you would rather use a pose file to impliment Outline display mode, this small pz2 will do it for the currently selected actor. It should work on magnets, props, body parts, lights, anything. The one condition is that there must be a figure in the scene.

{
//OUTLINE.pz2
version
 {
 number 5.00
 }
actor $CURRENT
 {
 displayMode EDGESONLY
 }
}

If you do want to use it with no figure in the scene, give it an MT5 file extension and save it to a 'materials' folder.