Game is Paused Menu shows up

Hi,

first, i already spend lots of time looking up previously ask questions. I even found many good answers. But unfortunately i am not able to achive exactly what i want.

What i want (for now):

When u click the mousebutton the game stops (i dont care about anything, but the mouselook. i dont want to look around navigating through the menu) and the menu shows up. Within the menu u can choose between different objekts u can choose materials for. When u cilick the mousebutton again everything disappears.

Now, all of that can be realy basic (normal gui buttons are enough). How i aready mentioned i already tried alot to achive that, and the whole part with the buttons and the menu works just fine. The biggest Problem i have is the game pause. I realy dont get, why its not working.

So here is the code i already put together.

 var isGamePaused : boolean = false;
 var material1 : Material;
 var material2 : Material;
 var material3 : Material;
 var material4 : Material;
 
 
 
 function Update() 
 {
 
 if(Input.GetKeyDown(KeyCode.Mouse0)){
       if(!isGamePaused){
             isGamePaused = true;
             GameObject.Find("First Person Controller").GetComponent("MouseLook").enabled = false;
             GameObject.Find("Main Camera").GetComponent("MouseLook").enabled = false;
       }
 }
 
 if(Input.GetKeyDown(KeyCode.Mouse0)){
       if (isGamePaused){
             isGamePaused = false;
             GameObject.Find("First Person Controller").GetComponent("MouseLook").enabled = true;
             GameObject.Find("Main Camera").GetComponent("MouseLook").enabled = true;
       }
 }
 }
 
 function OnGUI ()
 {
     if(isGamePaused)
     {
         if (GUI.Button(Rect (0,0, 100,50), "Boden"))
     {
         if(GameObject.Find("3d_daten__3d_Boden").renderer.sharedMaterial == material1)
        
                 GameObject.Find("3d_daten__3d_Boden").renderer.sharedMaterial = material2;
    
         else 
         
             GameObject.Find("3d_daten__3d_Boden").renderer.sharedMaterial = material1;
            
            
      }
      if (GUI.Button(Rect (100,0, 100,50), "Profile"))
     {
         
         if(GameObject.Find("3d_daten__3d_Profile").renderer.sharedMaterial == material3)
        
                     GameObject.Find("3d_daten__3d_Profile").renderer.sharedMaterial = material4;
        
         else 
         
                 GameObject.Find("3d_daten__3d_Profile").renderer.sharedMaterial = material3;
     }
     }
 }

Thanks in advance.

Stephan