Object reference not set to an instance of an object - error

Hi I´m new, and trying to solve a NullREference Problem.I searched, but couldnt get it done. It should be easy, i guess, but i just dont know much about c# ...but i can illustrate/animate. The game can be testplayed here (firefox and arrow keys): http://www.bertelot.de/unity/Furball2D_Testarea/Testbuild.html

Its the Prefab "Cloud" that is instantiated when jumping or boosting-down in-air. It works but i get errors (Object reference not set to an instance of an object) in three lines where it says:

cloudanim = GameObject.Find("Cloud").GetComponent(); ... cloudanim.Play("Boosting"); ... cloudanim.Play("Boosting");

So that cloudanim is the problem. I do not reference the instance of "Cloud".

Could you help me? Heres the script attached to the player:

 using UnityEngine;
 using System.Collections;
 
 public class PlayerController : MonoBehaviour {
     
     public float maxSpeed = 6f;
     public float jumpForce = 1000f;
     public Transform groundCheck;
     public LayerMask whatIsGround;
     public float verticalSpeed = 20;
     [HideInInspector]
     public bool lookingRight = true;
     bool doubleJump = false;
     public GameObject Boost;
     
     private Animator cloudanim;
     public GameObject Cloud;
 
 
     private Rigidbody2D rb2d;
     private Animator anim;
     private bool isGrounded = false;
 
 
     // Use this for initialization
     void Start () {
         rb2d = GetComponent<Rigidbody2D>();
         anim = GetComponent<Animator>();
 
     Cloud = GameObject.Find("Cloud");
     cloudanim = GameObject.Find("Cloud").GetComponent<Animator>();
 
     }
     
     // Update is called once per frame
     void Update () {
 
     if (Input.GetButtonDown("Jump") && (isGrounded || !doubleJump))
         {
             rb2d.AddForce(new Vector2(0,jumpForce));
 
             if (!doubleJump && !isGrounded)
             {
                 doubleJump = true;
                 Boost = Instantiate(Resources.Load("Prefabs/Cloud"), transform.position, transform.rotation) as GameObject;
                 cloudanim.Play("Boosting");
             
             }
 
         }
 
 
     if (Input.GetButtonDown("Vertical") && !isGrounded)
         {
             rb2d.AddForce(new Vector2(0,-jumpForce));
             Boost = Instantiate(Resources.Load("Prefabs/Cloud"), transform.position, transform.rotation) as GameObject;
             cloudanim.Play("Boosting");
         }
 
 
     }
 
 
     
     void FixedUpdate()
     {
         if (isGrounded) 
             doubleJump = false;
 
 
         float hor = Input.GetAxis ("Horizontal");
 
         anim.SetFloat ("Speed", Mathf.Abs (hor));
 
         rb2d.velocity = new Vector2 (hor * maxSpeed, rb2d.velocity.y);
           
         isGrounded = Physics2D.OverlapCircle (groundCheck.position, 0.15F, whatIsGround);
 
         anim.SetBool ("IsGrounded", isGrounded);
 
         if ((hor > 0 && !lookingRight)||(hor < 0 && lookingRight))
             Flip ();
          
         anim.SetFloat ("vSpeed", GetComponent<Rigidbody2D>().velocity.y);
     }
 
 
     
     public void Flip()
     {
         lookingRight = !lookingRight;
         Vector3 myScale = transform.localScale;
         myScale.x *= -1;
         transform.localScale = myScale;
     }
 
 }