Load scene when right click button is released not working

Hi,

In my game you are able to switch between two scenes using the right click button of a mouse.

When the right click button is pressed (and is held down) this loads scene 1 using this script:

  private var mouseDownStart:float;
  
  
  function Update () {
      if (Input.GetMouseButtonDown(1))
      {
          mouseDownStart = Time.time;
      }
      
      if (Input.GetMouseButton(1))
      {
          if ((Time.time - mouseDownStart) >= 3)
          {
       
              Application.LoadLevel(1);
         
          }
      }
  }

And in scene 1, when the right click button is released, I want scene 0 to load. At the moment I've tried using this script, but nothing happens when the right click button is released.

  private var mouseDownStart:float;
  
  
  function Update () {
      if (Input.GetMouseButtonUp(1))
      {
          mouseDownStart = Time.time;
     }
      
      if (Input.GetMouseButton(1))
      {
          if ((Time.time - mouseDownStart) >= 3)
          {
       
              Application.LoadLevel(1);
         
         }
      }
  }

Does anyone know if there's a way to load a scene when the right click button is released? (And if it is a problem that the button was initially pressed in a different scene?)

Best, Laurien

(I realise controlling the scene changes in this way sounds confusing - it's part of an art installation so I've actually rewired the right click button of a mouse to a different control panel, so it will make more sense when playing it)