Error #1010 issue

Question

I'm trying to finish this code for a class project, and I keep getting this "
TypeError: Error #1010: A term is undefined and has no properties.
    at ViolaMobileGameStudentsVersion_fla::MainTimeline/gameLoop()"
I've debugged it and it's said that the issue is at frame 86, which is
"menuScreen.level_txt.text = String(level);"
Here's the whole code, it's kind of long but I can't figure anything out. All the texts have their proper names.
Any suggestions are appreciated, I have to have this turned in by saturday..
import fl.transitions.Tween;
import fl.transitions.easing.*;
import fl.transitions.TweenEvent;
import flash.events.Event;
import flash.events.KeyboardEvent;
import flash.media.Sound;
import flash.net.SharedObject;
import flash.events.MouseEvent;
/**************VARIABLES**************/
var STATE_INIT_GAME:String = "STATE_INIT_GAME";
var STATE_START_PLAYER:String = "STATE_START_PLAYER";
var STATE_PLAY_GAME:String = "STATE_PLAY_GAME";
var STATE_END_GAME:String = "STATE_END_GAME";
var gameState:String;
var player:MovieClip;
var enemies:Array;
var level:Number;
var score:Number;
var lives:Number;
var Bullet:Array;
//var bulletTimer:Timer = new Timer(200);  // do not add this line
var explosions:Array;
var spaceKey:Boolean = false;
var rightKey:Boolean = false;
var leftKey:Boolean = false;
var upKey:Boolean = false;
var downKey:Boolean = false;
var accel:Accelerometer;
var hiddenOptions:Boolean = true;
/**************SETUP**************/
gameOverScreen.visible = false;
optionsMenu.visible = false;
stage.addEventListener(KeyboardEvent.KEY_DOWN, watchKeys);
stage.addEventListener(KeyboardEvent.KEY_UP, resetKey);
stage.addEventListener(KeyboardEvent.KEY_UP, optionsKey);
/**************INTRO SCREEN**************/
titleScreen.play_btn.addEventListener(MouseEvent.CLICK, clickAway);
function clickAway(event:MouseEvent):void
    moveScreenOff(titleScreen);
//Gesture Swipe
Multitouch.inputMode = MultitouchInputMode.GESTURE;
titleScreen.addEventListener(TransformGestureEvent.GESTURE_SWIPE, swipeAway);
function swipeAway(event:TransformGestureEvent):void
    //Swipe Left
    if (event.offsetX == -1)
        moveScreenOff(titleScreen);
function moveScreenOff(screen:MovieClip):void
    var introTween = new Tween(screen,"x",Strong.easeInOut,screen.x,(screen.width)*-1,1,true);
    introTween.addEventListener(TweenEvent.MOTION_FINISH, tweenFinish);
    function tweenFinish(e:TweenEvent):void
        gameState = STATE_INIT_GAME;
        addEventListener(Event.ENTER_FRAME, gameLoop);
we stopped here
/**************GAME STATES**************/
function gameLoop(e:Event):void
    menuScreen.level_txt.text = String(level);
    menuScreen.score_txt.text = String(score);
    menuScreen.lives_txt.text = String(lives);
    switch (gameState)
        case STATE_INIT_GAME :
            initGame();
            break;
        case STATE_START_PLAYER :
            startPlayer();
            break;
        case STATE_PLAY_GAME :
            playGame();
            break;
        case STATE_END_GAME :
            endGame();
            break;
/**************STATE_INIT_GAME**************/
function initGame():void
    player = new Player();
    enemies = new Array();
    Bullet = new Array();
    explosions = new Array();
    level = 1;
    score = 0;
    lives = 3;
    fire_btn.visible = true;
    gameState = STATE_START_PLAYER;
/**************STATE_START_PLAYER**************/
function startPlayer():void
    player.x = stage.stageWidth / 2;
    player.y = stage.stageHeight - player.height;
    player.cacheAsBitmap = true;
    addChild(player);
    accel = new Accelerometer();
    if (Accelerometer.isSupported)
        accel.addEventListener(AccelerometerEvent.UPDATE, accelMove);
    else
        //If there is no accelerometer support...
        addEventListener(Event.ENTER_FRAME, movePlayer);
    gameState = STATE_PLAY_GAME;
function accelMove(event:AccelerometerEvent):void
    player.x -=  event.accelerationX * 100;
    player.y +=  event.accelerationY * 80;
    if (player.x < 0)
        player.x = 0;
    else if (player.x > (stage.stageWidth - player.width) )
        player.x = stage.stageWidth - player.width;
    if (player.y < 50)
        player.y = 50;
    else if (player.y > stage.stageHeight - player.height)
        player.y = stage.stageHeight - player.height;
    addEventListener(MouseEvent.CLICK,fire);
function fire(evt:MouseEvent):void
    createBullet();
function movePlayer(Evt:Event):void
    if (rightKey)
        player.x +=  10;
    else if (leftKey)
        player.x -=  10;
    if (upKey)
        player.y -=  4;
    else if (downKey)
        player.y +=  4;
    if (spaceKey)
        createBullet();
    if (player.x < 0)
        player.x = 0;
    else if (player.x > stage.stageWidth - player.width)
        player.x = stage.stageWidth - player.width;
    if (player.y < 50)
        player.y = 50;
    else if (player.y > stage.stageHeight - player.height)
        player.y = stage.stageHeight - player.height;
function createBullet():void
    var tempBullet:MovieClip = new Bullets();
    tempBullet.x = player.x;
    tempBullet.y = player.y;
    tempBullet.cacheAsBitmap = true;
    tempBullet.speed = 15;
    addChild(tempBullet);
    Bullet.push(tempBullet);
function moveBullet():void
    var tempBullet:MovieClip;
    for (var i=Bullet.length-1; i>=0; i--)
        tempBullet = Bullet[i];
        tempBullet.y -=  tempBullet.speed;
        if (tempBullet.y < 0)
            removeBullet(i);
    var tempExplosion:MovieClip;
    for (i=explosions.length-1; i>=0; i--)
        tempExplosion = explosions[i];
        if (tempExplosion.currentFrame >= tempExplosion.totalFrames)
            removeExplosion(i);
/**************STATE_PLAY_GAME**************/
function playGame():void
    makeEnemies();
    moveEnemies();
    moveBullet();
    testForEnd();
function makeEnemies():void
    var chance:Number = Math.floor(Math.random() * 60);
    var whichEnemy:Number = Math.round(Math.random() * 2 + 1);
    if (chance <= 1 + level)
        var tempEnemy:MovieClip;
        tempEnemy = new Enemy();
        tempEnemy.gotoAndStop(whichEnemy);
        tempEnemy.speed = 3;
        tempEnemy.x = Math.round((Math.random() * 800) + 20);
        tempEnemy.cacheAsBitmap = true;
        addChild(tempEnemy);
        enemies.push(tempEnemy);
        setChildIndex(menuScreen,numChildren-1);
function moveEnemies():void
    var tempEnemy:MovieClip;
    for (var i:int =enemies.length-1; i>=0; i--)
        tempEnemy = enemies[i];
        tempEnemy.y +=  tempEnemy.speed;
        if (tempEnemy.y > stage.stageHeight)
            removeEnemy(i);
            lives--;
        else if (tempEnemy.hitTestObject(player))
            makeExplosion(tempEnemy.x, tempEnemy.y);
            removeEnemy(i);
            lives--;
        var tempBullet:MovieClip;
        //tempEnemy = enemies[i];
        for (var j:int=Bullet.length-1; j>=0; j--)
            tempBullet = Bullet[j];
            if (tempEnemy.hitTestObject(tempBullet))
                makeExplosion(tempEnemy.x, tempEnemy.y);
                removeEnemy(i);
                removeBullet(j);
                score +=  5;
function makeExplosion(ex:Number, ey:Number):void
    var tempExplosion:MovieClip;
    tempExplosion = new Explosion();
    tempExplosion.x = ex;
    tempExplosion.y = ey;
    addChild(tempExplosion);
    explosions.push(tempExplosion);
    //var sound:Sound = new Explode();
    //sound.play();
function testForEnd():void
    if (score > level * 100)
        level++;
    if (lives == 0)
        gameState = STATE_END_GAME;
function removeEnemy(idx:int)
    removeChild(enemies[idx]);
    enemies.splice(idx,1);
function removeBullet(idx:int)
    removeChild(Bullet[idx]);
    Bullet.splice(idx,1);
function removeExplosion(idx:int)
    removeChild(explosions[idx]);
    explosions.splice(idx,1);
/*********** KEY PRESS ***********/
function watchKeys(evt:KeyboardEvent):void
    if (evt.keyCode == Keyboard.SPACE)
        spaceKey = true;
    if (evt.keyCode == Keyboard.RIGHT)
        rightKey = true;
    if (evt.keyCode == Keyboard.LEFT)
        leftKey = true;
    if (evt.keyCode == Keyboard.UP)
        upKey = true;
    if (evt.keyCode == Keyboard.DOWN)
        downKey = true;
function resetKey(evt:KeyboardEvent):void
    if (evt.keyCode == Keyboard.SPACE)
        spaceKey = false;
    if (evt.keyCode == Keyboard.RIGHT)
        rightKey = false;
    if (evt.keyCode == Keyboard.LEFT)
        leftKey = false;
    if (evt.keyCode == Keyboard.UP)
        upKey = false;
    if (evt.keyCode == Keyboard.DOWN)
        downKey = false;
/**************END SCREEN**************/
function endGame():void
    accel.removeEventListener(AccelerometerEvent.UPDATE, accelMove);
    removeEventListener(Event.ENTER_FRAME, gameLoop);
    stage.removeEventListener(KeyboardEvent.KEY_DOWN, watchKeys);
    stage.removeEventListener(KeyboardEvent.KEY_UP, resetKey);
    fire_btn.enabled = false;
    fire_btn.visible = false;
    removeEventListener(MouseEvent.CLICK,fire);
    removeGame();
    gameOverScreen.visible = true;
    gameOverScreen.x = 0;
    showResults();
/**************REMOVE GAME**************/
function removeGame():void
    for (var i:int = enemies.length-1; i >=0; i--)
        removeEnemy(i);
    for (var j:int = Bullet.length-1; j >=0; j--)
        removeBullet(j);
    for (var k:int = explosions.length-1; k >=0; k--)
        removeExplosion(k);
    removeChild(player);
function showResults():void
    gameOverScreen.enter_btn.visible = false;
    gameOverScreen.nameField_txt.visible = false;
    var so:SharedObject = SharedObject.getLocal("alltimeHighScore");
    if (so.data.score == undefined || score > so.data.score)
        gameOverScreen.highScore_txt.text = "You made it to level " + level + " with a high score of " + score + ". \n Enter your name below.";
        gameOverScreen.enter_btn.visible = true;
        gameOverScreen.nameField_txt.visible = true;
    else
        gameOverScreen.highScore_txt.text = "Your score of " + score + " \n does not beat " + so.data.score + " \n by " + so.data.name;
    gameOverScreen.quit_btn.addEventListener(MouseEvent.CLICK, exitApp);
    gameOverScreen.enter_btn.addEventListener(MouseEvent.CLICK, clickEnter);
    function clickEnter(event:MouseEvent):void
        gameOverScreen.highScore_txt.text = "Great job, " + gameOverScreen.nameField_txt.text + "! \n You made it to level " + level + " \n with a score of " + score + "!";
        so.data.score = score;
        so.data.level = level;
        so.data.name = gameOverScreen.nameField_txt.text;
        so.flush();
        gameOverScreen.enter_btn.visible = false;
        gameOverScreen.nameField_txt.visible = false;
    //Enables the play button
    gameOverScreen.playAgain_btn.addEventListener(MouseEvent.CLICK, clickFinalAway);
    function clickFinalAway(event:MouseEvent):void
        moveScreenOff(gameOverScreen);
/**************OPTIONS MENU**************/
function optionsKey(event:KeyboardEvent):void
    //Options menu, use 16777234 or Keyboard.MENU
    if (event.keyCode == 16777234)
        if (hiddenOptions)
            setChildIndex(optionsMenu,numChildren-1);
            optionsMenu.visible = true;
            optionsMenu.addEventListener(MouseEvent.CLICK, exitApp);
            pauseGame();
        else
            optionsMenu.visible = false;
            optionsMenu.removeEventListener(MouseEvent.CLICK, exitApp);
            resumeGame();
        hiddenOptions = ! hiddenOptions;
function exitApp(event:MouseEvent):void
    //NativeApplication.nativeApplication.exit(0);
//Keep screen awake if you are using the Accelerometer etc.
//NativeApplication.nativeApplication.systemIdleMode = SystemIdleMode.KEEP_AWAKE;
stage.addEventListener(Event.DEACTIVATE, Deactivate);
function Deactivate(event:Event):void
    pauseGame();
stage.addEventListener(Event.ACTIVATE, Activate);
function Activate(event:Event):void
    resumeGame();
function pauseGame():void
    //Remove any listener events, timers etc.
    if (gameState == STATE_PLAY_GAME)
        removeEventListener(Event.ENTER_FRAME, gameLoop);
        accel.removeEventListener(AccelerometerEvent.UPDATE, accelMove);
        removeEventListener(MouseEvent.CLICK,fire);
function resumeGame():void
    //Activate any listener events, timers etc.
    if (gameState == STATE_PLAY_GAME)
        addEventListener(Event.ENTER_FRAME, gameLoop);
        accel.addEventListener(AccelerometerEvent.UPDATE, accelMove);
        addEventListener(MouseEvent.CLICK,fire);

Answer 1

I don't see where menuScreen is intialized...  It's also long after this was due, hope you figured it out.