Play button working on editor but not built game?

My play button which is a GUITexture in my main menu works on editor and directs me to the next scene, however the same button does not work once the game is built? Why can this be happening to me!?

Please I need help

Thanks

This is the code for the button

AudioListener.pause = false;
//do not pause audio 

var levelToLoad : String;
var QuitButton : boolean = false;
var music : AudioClip;
var a = true; 

var greenplay : GUITexture; 


function OnMouseDown() {


if (a == true)
{
audio.PlayOneShot(music);
Application.LoadLevel("Game");

}


}

function OnMouseEnter() {

greenplay.enabled = true; 

}


function OnMouseExit() {

greenplay.enabled = false; 

}

What is your target platform?

Does it give an error?

hey thanks I solved it and the audio variable wasn’t being used so I was getting a null reference error but I solved it now.