"tmpScale.y = Mathf.Lerp(tr.localScale.y, vScale, 5 * Time.deltaTime);"

if (tmpScale.y < 0.99 && Physics.Raycast (transform.position, Vector3.up, hit, 1.0f)){
Debug.DrawLine (transform.position, hit.point, Color.red);
}else tmpScale.y = Mathf.Lerp(tr.localScale.y, vScale, 5 * Time.deltaTime);
Debug.Log(tmpScale.y);

.....var useFixedUpdate : boolean = true;

var hit : RaycastHit;//!!!!!!!!!!!!!!!!!!!!!
var upp : Vector3;//!!!!!!!!!!!!!!!!!!!!!
              
var dist : float;
// For the next variables, @System.NonSerialized ....

...
function Awake () {
    controller = GetComponent (CharacterController);
    tr = transform;
    dist = controller.height/2;///!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
}
...

    ...if (useFixedUpdate)
     UpdateFunction();
        
if (Input.GetKey("c"))//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            { // press C to crouch//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
                vScale = 0.5f;//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            }//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
               
               
            var ultScale: float = tr.localScale.y; // crouch/stand up smoothly //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
               
            var tmpScale : Vector3 = tr.localScale;//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            var tmpPosition : Vector3 = tr.position;//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
               

           if (tmpScale.y < 0.99 && Physics.Raycast (transform.position, Vector3.up, hit, 1.0)){ //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
      Debug.DrawLine (transform.position, hit.point, Color.red);//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
     }else tmpScale.y = Mathf.Lerp(tr.localScale.y, vScale, 5 * Time.deltaTime);//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
             Debug.Log(tmpScale.y);//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            tr.localScale = tmpScale;//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
               
            tmpPosition.y += dist * (tr.localScale.y - ultScale); // fix vertical position        //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            tr.position = tmpPosition;//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
               
}

function Update () {
    if (!useFixedUpdate)
     UpdateFunction();
}

if (tmpScale.y < 0.99 && Physics.Raycast (transform.position, Vector3.up, hit, 1.0f)){  
Debug.DrawLine (transform.position, hit.point, Color.red);  
}else tmpScale.y = Mathf.Lerp(tr.localScale.y, vScale, 5 * Time.deltaTime);  
Debug.Log(tmpScale.y);