It is the same effector as the one in Johann's github repository (https://github.com/jcrocholl/kossel) just without the part that the push fit would screw into. If you want to modify the included scad, you need to replace any references to configuration.scad or put configuration.scad (https://github.com/jcrocholl/kossel/blob/master/configuration.scad) in the same directory as effector.scad.