Fast moving objects 2D game

Hey guys!

I find the official unity training https://www.youtube.com/watch?v=D5MqLcO6A8g and find bug.(look at the score)

I spent about 2 days to fix it and failed. I find the script http://wiki.unity3d.com/index.php?title=DontGoThroughThings and try to rewrite to use in 2D. Failed again)

Please help me!

This is rewrite script:

 using UnityEngine;
 using System.Collections;
 
 public class DontGoThroughThings2D : MonoBehaviour {
 
     public LayerMask layerMask; //make sure we aren't in this layer 
     public float skinWidth; //probably doesn't need to be changed 
     
     private float minimumExtent; 
     private float partialExtent; 
     private float sqrMinimumExtent; 
     private Vector2 previousPosition; 
     private Rigidbody2D myRigidbody; 
     
     
     //initialize values 
     void Awake() 
     { 
         myRigidbody = GetComponent<Rigidbody2D>(); 
         previousPosition = myRigidbody.position;
         minimumExtent = Mathf.Min(Mathf.Min(GetComponent<Collider2D>().bounds.extents.x, GetComponent<Collider2D>().bounds.extents.y)); 
         partialExtent = minimumExtent * (1.0f - skinWidth); 
         sqrMinimumExtent = minimumExtent * minimumExtent; 
     } 
     
     void FixedUpdate() 
     { 
         //have we moved more than our minimum extent? 
         Vector2 movementThisStep = myRigidbody.position - previousPosition; 
         float movementSqrMagnitude = movementThisStep.sqrMagnitude;
         
         if (movementSqrMagnitude > sqrMinimumExtent) 
         { 
             float movementMagnitude = Mathf.Sqrt(movementSqrMagnitude);
             //RaycastHit2D hitInfo; 
             
             //check for obstructions we might have missed 
             if (Physics2D.Raycast(previousPosition, movementThisStep, movementMagnitude, 0, layerMask.value)) 
                 myRigidbody.position = (movementThisStep/movementMagnitude)*partialExtent;
             Debug.DrawLine(myRigidbody.position, myRigidbody.position - previousPosition, Color.green);
         } 
         
         previousPosition = myRigidbody.position; 
     }
 }
 

This is unitypackage https://www.dropbox.com/s/a3n1dalbc1k0k42/Hat%20Trick.unitypackage?dl=0

P.S. Sorry for my english and thank you for help!!