Zig Zag Shape & Order

Rendering calculations start from the top and go down. You have the layer on top, masks, effects, layer styles, and transformations. If you need to change the order, you pre-compose. Collapsing Transformations allow you to access layer properties before other effects have been applied. That is why collapse transformations let the main comp camera and lights work on 3D layers in a pre-comp.

When ZigZag is above the line, there is nothing to modify. The line has to be created before you can modify it.