GUI Error: You are pushing more GUIClips than you are popping. Make sure they are balanced) Help!!!

i am making a game on unity back got this message after i had finished the code. this peice of code is from http://speed-tutor.com/survival-series/ and download the file. it is under GUI and it is the code txt.

Thx for any advise.

 #pragma strict
 
 //Size of Textures
 
 var size : Vector2 = new Vector2(240, 40);
 
 //Health Variables
 var healthPos : Vector2 = new Vector2(20, 20);
 var healthBarDisplay : float = 1;
 var healthBarEmpty : Texture2D;
 var healthBarFull : Texture2D;
 
 //Hunger Variables
 var hungerPos : Vector2 = new Vector2(20, 60);
 var hungerBarDisplay : float = 1;
 var hungerBarEmpty : Texture2D;
 var hungerBarFull : Texture2D;
 
 //Thirst Variables
 var thirstPos : Vector2 = new Vector2(20, 100);
 var thirstBarDisplay : float = 1;
 var thirstBarEmpty : Texture2D;
 var thirstBarFull : Texture2D;
 
 //Stamina Variables
 var staminaPos : Vector2 = new Vector2(20, 140);
 var staminaBarDisplay : float = 1;
 var staminaBarEmpty : Texture2D;
 var staminaBarFull : Texture2D;
 
 //Fall Rate
 var healthFallRate : int = 150;
 var hungerFallRate : int = 150;
 var thirstFallRate : int = 100;
 var staminaFallRate : int = 35;
 
 private var chMotor : CharacterMotor;
 private var controller : CharacterController;
 
 var canJump : boolean = false;
 
 var jumpTimer : float = 0.7;
 
 function Start()
 {
     chMotor = GetComponent(CharacterMotor);
     controller = GetComponent(CharacterController);
 }
 
 function OnGUI()
 {
     //Health GUI
     GUI.BeginGroup(new Rect (healthPos.x, healthPos.y, size.x, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), healthBarEmpty);
     
     GUI.BeginGroup(new Rect (0, 0, size.x * healthBarDisplay, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), healthBarFull);
     
     GUI.EndGroup();
     GUI.EndGroup();
     
     //Hunger GUI
     GUI.BeginGroup(new Rect (hungerPos.x, hungerPos.y, size.x, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), hungerBarEmpty);
     
     GUI.BeginGroup(new Rect (0, 0, size.x * hungerBarDisplay, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), hungerBarFull);
     
     GUI.EndGroup();
     GUI.EndGroup();
     
     //Thirst GUI
     GUI.BeginGroup(new Rect (thirstPos.x, thirstPos.y, size.x, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), thirstBarEmpty);
     
     GUI.BeginGroup(new Rect (0, 0, size.x * thirstBarDisplay, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), thirstBarFull);
     
     GUI.EndGroup();
     GUI.EndGroup();
     
     //Stamina GUI
     GUI.BeginGroup(new Rect (staminaPos.x, staminaPos.y, size.x, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), staminaBarEmpty);
     
     GUI.BeginGroup(new Rect (0, 0, size.x * staminaBarDisplay, size.y));
     GUI.Box(Rect(0, 0, size.x, size.y), staminaBarFull);
     
     GUI.EndGroup();
     GUI.EndGroup();
 }
 
 function Update()
 {
     //HEALTH CONTROL SECTION
     if(hungerBarDisplay <= 0 && (thirstBarDisplay <= 0))
     {
         healthBarDisplay -= Time.deltaTime / healthFallRate * 2;
     }
     
     else
     {
         if(hungerBarDisplay <= 0 || thirstBarDisplay <= 0)
         {
             healthBarDisplay -= Time.deltaTime / healthFallRate;
         }
     }
     
     if(healthBarDisplay <= 0)
     {
         CharacterDeath();
     }
     
     //HUNGER CONTROL SECTION
     if(hungerBarDisplay >= 0)
     {
         hungerBarDisplay -= Time.deltaTime / hungerFallRate;
     }
     
     if(hungerBarDisplay <= 0)
     {
         hungerBarDisplay = 0;
     }
     
     if(hungerBarDisplay >= 1)
     {
         hungerBarDisplay = 1;
     }
     
     //THIRST CONTROL SECTION
     if(thirstBarDisplay >= 0)
     {
         thirstBarDisplay -= Time.deltaTime / thirstFallRate;
     }
     
     if(thirstBarDisplay <= 0)
     {
         thirstBarDisplay = 0;
     }
     
     if(thirstBarDisplay >= 1)
     {
         thirstBarDisplay = 1;
     }
     
     //STAMINA CONTROL SECTION
     if(controller.velocity.magnitude > 0 && Input.GetKey(KeyCode.LeftShift))
     {
         chMotor.movement.maxForwardSpeed = 10;
         chMotor.movement.maxSidewaysSpeed = 10;
         staminaBarDisplay -= Time.deltaTime / staminaFallRate;
     }
     
     else
     {
         chMotor.movement.maxForwardSpeed = 6;
         chMotor.movement.maxSidewaysSpeed = 6;
         staminaBarDisplay += Time.deltaTime / staminaFallRate;
     }
     
     //JUMPING SECTION
     if(Input.GetKeyDown(KeyCode.Space) && canJump == true)
     {
         staminaBarDisplay -= 0.2;
         Wait();
     }
     
     if(canJump == false)
     {
         jumpTimer -= Time.deltaTime;
         chMotor.jumping.enabled = false;
     }
     
     if(jumpTimer <= 0)
     {
         canJump = true;
         chMotor.jumping.enabled = true;
         jumpTimer = 0.7;
     }
     
     //COMMENTED THESE SECTIONS OUT - UPDATED 16/07/14
     //if(staminaBarDisplay <= 0.05)
     //{
         //canJump = false;
         //chMotor.jumping.enabled = false;
     //}
     
     //else
     //{
         //canJump = true;
         //chMotor.jumping.enabled = true;
     //}
     
     if(staminaBarDisplay >= 1)
     {
         staminaBarDisplay = 1;
     }
     
     if(staminaBarDisplay <= 0)
     {
         //ADDED line 181 here!
         staminaBarDisplay = 0;
         canJump = false;
         chMotor.jumping.enabled = false;
         chMotor.movement.maxForwardSpeed = 6;
         chMotor.movement.maxSidewaysSpeed = 6;
     }
 }
 
 function CharacterDeath()
 {
     Application.LoadLevel("SIMPLELEVEL");
 }
 
 function Wait()
 {
     yield WaitForSeconds(0.1);
     canJump = false;
 }