Javascript not working for Imported Assests

Hi, this is my first post on this site and I’m a complete beginner to Scripting, so I need your help please!

I found/modified the code below to allow for the mouse to drag and rotate an object.

It works perfectly on the Built-In assests, but when Import my own Assets from Cinema 4D, add the Script Component to the Imported Assest, nothing happens.

Do I need to adjsut something for Mesh objects? I tried placing the imported assest as a Child of an Empty Game Object, but still no movement when Playing the scene.

**Edit: my problem might be with Mesh objects. Every Script I write works with built in Assests, but not my imported Meshes :S

Thanks in advance

var rotationSpeed = 10.0;
var lerpSpeed = 6.0;

 private var speed = new Vector3();
 private var avgSpeed = new Vector3();
 private var dragging = false;
 private var targetSpeedY = new Vector3();
 
 function OnMouseDown() 
 {
     dragging = true;
 }

  function OnMouseUp() 
 {
     dragging = false;
 }
  
 function Update () 
 {
 
     if (dragging) {
         speed = new Vector3(-Input.GetAxis ("Mouse X"), Input.GetAxis("Mouse Y"), 0);
         avgSpeed = Vector3.Lerp(avgSpeed,speed,Time.deltaTime * 5);
     } else {
         if (dragging) {
             speed = avgSpeed;
             dragging = false;
         }
         var i = Time.deltaTime * lerpSpeed;
         speed = Vector3.Lerp( speed, Vector3.zero, i);   
     }
 
     transform.Rotate(Vector3.up, speed.x * rotationSpeed, Space.World);
	 transform.Rotate(Vector3.forward, speed.y * rotationSpeed, Space.World);
	 transform.Rotate(Vector3.right, speed.y * rotationSpeed, Space.World);	
 }

Change your Update like this
function Update ()
{

      if (dragging) {
          speed = new Vector3(-Input.GetAxis ("Mouse X"), Input.GetAxis("Mouse Y"), 0);
          avgSpeed = Vector3.Lerp(avgSpeed,speed,Time.deltaTime * 5);
      } else {
              speed = avgSpeed;
              dragging = false;          var i = Time.deltaTime * lerpSpeed;
          speed = Vector3.Lerp( speed, Vector3.zero, i);   
      }
  if(Input.GetMouseButtonDown(0))
  {
      transform.Rotate(Vector3.up, speed.x * rotationSpeed, Space.World);
      transform.Rotate(Vector3.forward, speed.y * rotationSpeed, Space.World);
      transform.Rotate(Vector3.right, speed.y * rotationSpeed, Space.World);  
  }  
  }