I'm curious is it ok for me to comment out the lines as below in UIDraggableCamera.cs? It works fine as such for me, but I'm not sure why it was meant to throw error.
void Awake ()
{
mCam = camera;
mTrans = transform;
//if (rootForBounds == null)
//{
//Debug.LogError(NGUITools.GetHierarchy(gameObject) + " needs the 'Root For Bounds' parameter to be set", this);
//enabled = false;
//}
}