Trying to access a shader property - Silhouette Outlined Diffuse

Hello

I have downloaded the Silhouette Outlined Shader from wiki to add an Outline Shader for my gameobjects.
I am trying to access its properties to change them dynamically during run time.

I have the code below but it is not working.

Any advices on how to do it?

Code (CSharp):

1.     public Renderer outline;
2.  
3.     void Start () {
4.         Renderer outline = GetComponent<Renderer>();
5.         outline.material.shader = Shader.Find("Outlined/Silhouetted Bumped");
6.     }
7.  
8.     void Update () {
9.         float test = Mathf.PingPong(Time.time, 0.1f);
10.         outline.material.SetFloat("_Outline", test);
11.     }
12. }