Rotate an object with blendshapes

Hi, I have a 3D object with blendshapes attached that I imported from Maya. I am trying to get the object's x and y position to rotate as user drags the mouse. Here is the script I am using below. It works on a regular unity 3d game object but won't work on my blendhshape object. I parented the blendshape object to an empty game object and tried attaching the script to the parent but still doesn't work. using UnityEngine; using System.Collections;

public class RotateObj : MonoBehaviour {

 public GameObject target;

 
 public float spinDurationFactor = 1.0f;

 
 public float xSpinDeltaFactor = 1f;
 
 public float ySpinDeltaFactor =1f;

 private float mouseXInitial;
 private float mouseXCurrent;
 private float mouseYInitial;
 private float mouseYCurrent;
 private float deltaX;
 private float deltaY;

 // Use this for initialization
 void Start () {}


 // Update is called once per frame
 public void Update () {}
 

 
 void OnMouseDown()
 {
     // Record initial mouse position
     mouseXInitial = Input.mousePosition.x;
     mouseYInitial = Input.mousePosition.y;
 }
 void OnMouseDrag()
 {
     
     mouseXCurrent = Input.mousePosition.x;

     
     deltaX = (mouseXCurrent - mouseXInitial) * xSpinDeltaFactor;

     
     if (mouseXCurrent != mouseXInitial)
     {
         
         target.transform.RotateAround(Vector3.zero, Vector3.up, -deltaX);
     }

     
     mouseXInit = Input.mousePosition.x;



     
     mouseYCurrent = Input.mousePosition.y;

     
     deltaY = (mouseYCurrent - mouseYInitial ) * ySpinDeltaFactor;

     
     if (mouseYCurrent != mouseYInitial)
     {
         
         target.transform.RotateAround(Vector3.zero, Vector3.right, deltaY);
     }

     
     mouseYInitial = Input.mousePosition.y;
 }
 void OnMouseUp()
 {
     
     StartCoroutine(spinDown());
 }

 
     
     float l = Mathf.Floor(spinDurationFactor * (Mathf.Abs(deltaX)>Mathf.Abs(deltaY) ? Mathf.Abs(deltaX):Mathf.Abs(deltaY)) + 0.0f);

     float currentSpeedX;
     float currentSpeedY;
     for (int j = 0; j < (int)l; j++)
     {
         currentSpeedX = ((Mathf.Cos(j/((int)l/Mathf.PI)) + 1.0f)/2.0f) * deltaX;
         //currentSpeedX = -Mathf.Log(j/l) * deltaX;
         target.transform.RotateAround(Vector3.zero, Vector3.up, -currentSpeedX);

         currentSpeedY = ((Mathf.Cos(j/((int)l/Mathf.PI)) + 1.0f)/2.0f) * deltaY;
         //currentSpeedY = -Mathf.Log(j/l) * deltaY;
         target.transform.RotateAround(Vector3.zero, Vector3.right, currentSpeedY);
         yield return new WaitForSeconds(0.01f);
     }
 }

 .
 public IEnumerator smoothReorient(Quaternion _finalOrientation, float _framesCount) {
     float frames = _framesCount;
     Quaternion from = target.transform.localRotation;
     Quaternion to = _finalOrientation;
     float t;
     for (int j = 0; j < (int)frames; j++)
     {
         t = ((Mathf.Cos(j/(frames/Mathf.PI)) + 1.0f)/2.0f);
         target.transform.localRotation = Quaternion.Slerp(from, to, 1 - t);
         yield return new WaitForSeconds(0.01f);
     }
 }