A Unity ID allows you to buy and/or subscribe to Unity products and services, shop in the Asset Store and participate
in the Unity community.
I know the post is old (considering the development of Unity UI) but to those still in doubt:
SetSelectedGameObject also works with one argument...
Thanks, the Physics Material worked for me.
I am working with Toolkit2D combined with Unity 2D Physics.
Part of my walls are actually tiles...