Hello, I am trying to write a function which will create a visual vector on a rigidbody. Then this vector can be rotated with mouse. When vecotr rotation is finished a force is added to that rigidbody. My code is not working and I'd like to hear tips and suggestions. Thanks in advance for your answers.

var arrowPrefab : GameObject;
var speed : int;
var forceMultiplyer : float;

private var arrowInstance : GameObject;

function Update () {
    if (Input.GetMouseButton(1)) {
       if (arrowInstance == null) {
         arrowInstance = Instantiate(arrowPrefab, transform.position, Quaternion.identity);
       }
       else {
         if (Input.GetMouseButton(0)) {
          arrowInstance.transform.Rotate(0, 0, Input.GetAxis("Mouse Y") * Time.deltaTime * speed);
         }
         else {
          arrowInstance.transform.Rotate(Vector3(Input.GetAxis("Mouse Y"), Input.GetAxis("Mouse X"), 0) * Time.deltaTime * speed);
         }
       }
    }

    if (Input.GetMouseButtonUp(1)) {
       if (arrowInstance != null) {   
         var forceVector : Vector3 = new Vector3(forceMultiplyer,
                                  forceMultiplyer,
                                  forceMultiplyer);

         rigidbody.AddForce(arrowInstance.transform.rotation * forceVector);
         Destroy(arrowInstance);
       }
    }
}