When my project is built my polygon collider does not change.

Questions & Answers
1

In the editor everything works perfectly, including the faulty PG collier. It goes to ducking mode when you Duck, and normal mode when you are not. When it is built however, it only ever stays in its normal mode.
If it helps here is my code:

using UnityEngine;
using UnityEngine.UI;
using System.Collections; 
public class Player_Controls : MonoBehaviour {
    public float speed, Jump, SpeedIncreaseIncriments, DuckingTime;
    public GameObject Death_TapToRestart, Death_Quit, Death_Pick;
    [HideInInspector]
    public bool canMove = true, canJump = false;
    //Ducking is for Phones
    bool CanDuck = true, Ducking = false;
    float ypos;
    Animator anim;
    PolygonCollider2D PG;
    [HideInInspector]
    public Vector2[] WalkingPoints, DuckingPoints;
    [HideInInspector]
    public int Option;

    float DuckingTIME;
 void Start() {
        DuckingTIME = DuckingTime;
        PG = GetComponent<PolygonCollider2D>();
        anim = GetComponent<Animator>();
        canMove = true;
        ypos = transform.position.y;
    }
    //Changes Speed
    void Speed() {
        if (Mathf.Round(transform.position.x % 100) == 0) {
            speed += SpeedIncreaseIncriments;
        }
    }
    //Sees if you are dead.
    void OnCollisionEnter2D(Collision2D col) {
        if (col.gameObject.layer == 9) {
            canMove = false;
        }
    }
    void Update() {
        if (canMove) {
            //Are you on the ground?
            if (transform.position.y <= ypos) {
                //yes
                canJump = true;
            } else {
                //no
                canJump = false;
            }
            //Falling through the World?
            if (transform.position.y <= -5) {
                canMove = false;
            }


          //  #if UNITY_EDITOR || UNITY_STANDALONE || UNITY_WEBPLAYER

            //Key Binded!
            DUCK();
            //Key Binded!
            JUMP();

            //#else 

            //Swipe Controls       
            if (Swiping()== "Jump") {
                if (canJump) {
                    GetComponent<Rigidbody2D>().AddForce(new Vector2(0, Jump));
                }
            }
            if (Swiping()=="Drag") {
                Ducking = true;
            }

            if(Swiping() == "unDuck") { 
                Ducking = false;
            }
            



            if (Ducking) {
                PG.SetPath(0, DuckingPoints);
                anim.SetBool("Ducking", true);
                DuckingTime -= Time.deltaTime;
                if (DuckingTime <= 0) {
                    DuckingTime = DuckingTIME;
                    anim.SetBool("Ducking", false);
                    PG.SetPath(0, WalkingPoints);
                    Ducking = false;
                }
            }                  
 //           #endif


            //UI STuff
            Death_TapToRestart.SetActive(false);
            Death_Quit.SetActive(false);
            Death_Pick.SetActive(false);
            //End UI Stuff
            anim.SetBool("Dead", false);
            Camera.main.transform.Translate(new Vector3(speed * Time.deltaTime, 0, 0));
            transform.Translate(new Vector3(speed * Time.deltaTime, 0, 0));
        } else {
            //UI 
            Death_TapToRestart.SetActive(true);
            Death_Quit.SetActive(true);
            Death_Pick.SetActive(true);
            //End UI Stuff
            anim.SetBool("Dead", true);
            //                GameObject.Find("World Generator").GetComponent<World_Generation>().Restart();
            
        }
    }


    private Vector2 touchOrigin = -Vector2.one;
    string Swiping() {
        float y = 0;
        if (Input.touchCount > 0) {
            Touch myTouch = Input.touches[0];
            if (myTouch.phase == TouchPhase.Began) {
                touchOrigin = myTouch.position;
            } else if (myTouch.phase == TouchPhase.Ended && touchOrigin.x >= 0) {
                Vector2 TouchEnd = myTouch.position;
                y = TouchEnd.y - touchOrigin.y;
                if (y <= -10f) {
                    return "Drag";
                }
                if (y >= 10f) {
                    return "Jump";
                }
                return "Jump";
            }
        }
        return null;
    }
    void JUMP() {
        if (canJump) {
            if (Input.GetButton("Jump")) {
                GetComponent<Rigidbody2D>().AddForce(new Vector2(0, Jump));
            }
        }
    }
    //Keybinded Duck
    void Duck() {
        if (Input.GetButton("Duck")) {
            anim.SetBool("Ducking", true);
            PG.SetPath(0, DuckingPoints);
        }
        if (Input.GetButtonUp("Duck")) {
            anim.SetBool("Ducking", false);
            PG.SetPath(0, WalkingPoints);
        }
    }
    void DUCK() {
        if (CanDuck) {
            Duck();
        }
    }
}
2

I have fixed it myself thanks to this link:
https://www.reddit.com/r/Unity2D/comments/2ge8h0/altering_a_polygon_collider_at_runtime/
and this comment:
IMPORTANT: If you want to modify Polygon Colliders based on the shape of a sprite at runtime make sure you set the sprite to “Advanced” and check off “Readable”. If you don’t do this the collider will work in the editor but not in any builds.

I learned this during the last hour of a game jam when all my colliders broke in the web build…