Why doesn't the build version of my game work as the preview does ?

When I build my game to play on a mac or a pc it doesn’t work as it does in the preview !

The game is simple , you fly an eagle around an island looking for spheres , when you touch the sphere the sphere disappears and an audio source plays to indicate you have successfully hit the sphere .

once you have found all 12 Spheres a new level loads and you hunt for 12 more Spheres , I have 5 levels to the game .

It works just fine when I preview the game in unity but when I build to either MAC or PC , when the eagle hits a sphere it doesn’t disappear and the audio source doesn’t play the sphere moves away and keeps moving . So the game can’t ever go to the next level .

This is a version of the pickup script I have modified to do this any ideas why it is not working in the build versions ?

using UnityEngine;
using System.Collections;

public class pickUps : MonoBehaviour {

public float  speed;
public float  levelUp;
public GUIText countText;
public GUIText winText;
public AudioClip droplet;
private int count;
private AudioSource source;

void Start ()
{
	source = GetComponent<AudioSource>();
	count = 0;
	winText.text = "test";
	levelUp = 12;
	SetCountText ();

}

void FixedUpdate ()
{
	gameObject.GetComponent<Renderer>().material.color = Color.green;
	float moveHorizontal = Input.GetAxis("Horizontal");
	float moveVertical = Input.GetAxis("Vertical");

	Vector3 movement = new Vector3 (moveHorizontal, 0.0f, moveVertical);

	GetComponent<Rigidbody>().AddForce(movement*speed);

}

void OnTriggerEnter(Collider other) 
{
	if(other.gameObject.tag == "PickUp") 
	{
		other.gameObject.SetActive(false);
		count = count + 1;
		SetCountText ();
		source.PlayOneShot(droplet,1f);

	}
}
void SetCountText ()
{
	countText.text = "Count: " + count.ToString();
	if(count >= levelUp)
	{
		int i = Application.loadedLevel;
		Application.LoadLevel(i + 1);
		winText.text = "Task completed  - Press Escape to Quit";

	}
}

}

Application.LoadLevel is obsolete use SceneManager.LoadScene(indexOfLevel); (you need to write using UnityEngine.SceneManagement;)
I don´t see any reason why your pickUp script would not work. Have you saved everything and rebuilt it again?