If you are having problems with using the addon in Blender 2.78 then download 2.77 again. It's not much worse and the addon will work normally. Also make sure to set the grease pencil to object and cut in ortho for precise cuts. happy blending :)
Thank u a lot! Was searching for the reason why its not working for a very long time and got super demotivated. »... set the grease pencil to object ...« saved my day! :D
