what should I do after downloading model by asset bundle

Hi all,

I am trying to use AssetBundle but I got a problem. On  AssetBundleAugmenter.cs like above:

public class AssetBundleAugmenter : MonoBehaviour, ITrackableEventHandler  {

	public string AssetName;
	public int Version;
	private GameObject mBundleInstance = null;
	private TrackableBehaviour mTrackableBehaviour;
	private bool mAttached = false;
	public bool targetIsFound = false;

	void Start() {
		StartCoroutine(DownloadAndCache());
		mTrackableBehaviour = GetComponent<TrackableBehaviour>();
		if (mTrackableBehaviour) {
			mTrackableBehaviour.RegisterTrackableEventHandler(this);
		}
	}

	void Update(){

		if (targetIsFound) {
			StartCoroutine (DownloadAndCache ());
			mTrackableBehaviour = GetComponent<TrackableBehaviour> ();
			if (mTrackableBehaviour) {
					mTrackableBehaviour.RegisterTrackableEventHandler (this);
			}
			targetIsFound = false;
		}
	}
	
	// Update is called once per frame
	IEnumerator DownloadAndCache() {
		while(!Caching.ready)
			yield return null;
		// example URL of file on PC filesystem (Windows)
		// string bundleURL = "file:///D:/Unity/AssetBundles/MyAssetBundle.unity3d";
		// example URL of file on Android device SD-card
		string bundleURL = "http://17.16.71.1/3dmodel/agentwalking.unity3d";
		using (WWW www = WWW .LoadFromCacheOrDownload(bundleURL, Version)) {
			yield return www;
			if (www .error != null)
				throw new UnityException("WWW Download had an error: " + www .error);
			AssetBundle bundle = www .assetBundle;
			if (AssetName == "") {
				mBundleInstance = Instantiate (bundle.mainAsset) as GameObject;
			}
			else {
				mBundleInstance = Instantiate(bundle.Load (AssetName)) as GameObject;
			}
		}
	}
	public void OnTrackableStateChanged(
		TrackableBehaviour.Status previousStatus,
		TrackableBehaviour.Status newStatus) {
		if (newStatus == TrackableBehaviour.Status.DETECTED ||
		    newStatus == TrackableBehaviour.Status.TRACKED ||
		    newStatus == TrackableBehaviour.Status.EXTENDED_TRACKED) {
			if (!mAttached && mBundleInstance) {
				// if bundle has been loaded, let's attach it to this trackable
				mBundleInstance.transform.parent = this.transform;
				mBundleInstance.transform.localScale = new Vector3(0.3f, 0.3f, 0.3f);
				mBundleInstance.transform.localPosition = new Vector3(0.0f, 0.15f, 0.0f);
				mBundleInstance.transform.gameObject.SetActive(true);
				//mBundleInstance.animation.Play ("agentwalking"); 

				Debug.Log("OnTrackableStateChanged_____AssetBundleAugmenter: ");
				mBundleInstance.transform.Rotate (Vector3.up * 15 * Time.deltaTime);
				mAttached = true;
			}
		}
	}
}

agentwalking.unity3d is created by Prefab ( drag ImageTarget from Hierarchy to Project then BuildAssetBundle ). Prefag ImageTarget has child that called agentwalk . See image attached.

And this is my SimpleCloudHandler.cs:

public class SimpleCloudHandler : MonoBehaviour, ICloudRecoEventHandler  {
	private CloudRecoBehaviour mCloudRecoBehaviour;
	private bool mIsScanning = false;
	public ImageTargetBehaviour ImageTargetTemplate;
	private string mTargetMetadata = "";
	GameObject  agentwalk; 
	
	// Use this for initialization
	void Start () {
		agentwalk = GameObject.Find ("agentwalk");

		// register this event handler at the cloud reco behaviour
		mCloudRecoBehaviour = GetComponent<CloudRecoBehaviour>();
		if (mCloudRecoBehaviour)
		{
			mCloudRecoBehaviour.RegisterEventHandler(this);
		}
	}
	 

	void Update(){
		agentwalk.animation.Play ("agentwalking");
	}
	
	public void OnInitialized() {
		Debug.Log ("Cloud Reco initialized");
	}
	public void OnInitError(TargetFinder.InitState initError) {
		Debug.Log ("Cloud Reco init error " + initError.ToString());
	}
	public void OnUpdateError(TargetFinder.UpdateState updateError) {
		Debug.Log ("Cloud Reco update error " + updateError.ToString());
	}
	
	public void OnStateChanged(bool scanning) {
		mIsScanning = scanning;
		if (scanning)
		{
			// clear all known trackables
			ObjectTracker ot = TrackerManager.Instance.GetTracker<ObjectTracker>();
			ot.TargetFinder.ClearTrackables(false);
		}
	}
	
	// Here we handle a cloud target recognition event
	public void OnNewSearchResult(TargetFinder.TargetSearchResult targetSearchResult) {
		// do something with the target metadata
		mTargetMetadata = targetSearchResult.MetaData;
		// stop the target finder (i.e. stop scanning the cloud)
		mCloudRecoBehaviour.CloudRecoEnabled = false;
		
		// Build augmentation based on target
		if (ImageTargetTemplate) {
			// enable the new result with the same ImageTargetBehaviour:
			ObjectTracker tracker = TrackerManager.Instance.GetTracker<ObjectTracker>();
			ImageTargetBehaviour imageTargetBehaviour =
				(ImageTargetBehaviour)tracker.TargetFinder.EnableTracking(
					targetSearchResult, ImageTargetTemplate.gameObject);
		}
	}
	
	void OnGUI() {
		// Display current 'scanning' status
		GUI.Label (new Rect (50,50,150,50), mTargetMetadata);
		// If not scanning, show button
		// so that user can restart cloud scanning
		if (!mIsScanning) {
			if (GUI.Button(new Rect(50,100,120,50), "Rescan")) {
				// Restart TargetFinder
				mCloudRecoBehaviour.CloudRecoEnabled = true;
			} 
		}  
	}
}

My questions:

1. Do Vuforia SDK auto sync after AssetBundle downloading model (.unity3d) ? More explain, Is "agentwalk"  found after download?

2. What should I do on SimpleCloudHandler.cs to use model downloaded?