Help please!

I have a project due in a week, and I’m lost! :*(
I’m having a lot of troubles with action script since most of the project is based on self learning. :puzzled:

Part of the project is a game attached to an interactive representation of the blood components for children (it’s a very minimal representation).
The game consists of 4 objects, one of them is player controlled (WCell), and the other 3 are supposed to randomly fall -top to bottom-, the player gets points for “eating” the correct object(germs), and loses points for eating the wrong objects(tasiyot_MC & RCell_mc).

I’m attaching the code (also zipped fla file) here, hoping that someone in this huge forum could help me find out why am I receiving this error:

TypeError: Error #1010: A term is undefined and has no properties.
at MethodInfo-2() :ponder:

Thank you much in advance! :smiley:

//beginning----------------------------------------

var score:Number=0;
this.dyna.text=String(score);
//score textbox--------------

var xrand:Number=Math.round(Math.random()(540-1)+1);
//Random x positioning-----------------------------------
var yrand:Number=Math.round(Math.random()
(5-1)+1);
//Random fall speed--------------------------------------

but1.addEventListener(MouseEvent.CLICK,global);
//start game-----------------------------------------
function global(event:MouseEvent):void {
if (score==200) {
this.instr.visible=true;
this.instr.text=“YOU WIN”;
stop();
//winning msg and stop-----------------------------
} else {

this.instr.visible=false;
//hide instructions textbox

stage.addEventListener(KeyboardEvent.KEY_DOWN,Move WCell);
//move the white cell listener----------------------------

germs.addEventListener(Event.ENTER_FRAME,fall);
//call the top to bottom objects fall-----------

RCell_mc.addEventListener(Event.ENTER_FRAME,fall);
//call the top to bottom objects fall--------------

tasiyot_MC.addEventListener(Event.ENTER_FRAME,fall );
//call the top to bottom objects fall-----------------

function fall(event:Event):void {
//top to bottom fall-loop start---------------------------
this.RCell_mc.y=yrand;
if (this.RCell_mc.y>399) {
this.RCell_mc.x==xrand;
this.RCell_mc.y==0;
//top to bottom object fall-loop------------------
}

this.tasiyot_MC.y=yrand;
if (this.tasiyot_MC.y>399) {
this.tasiyot_MC.y==0;
this.tasiyot_MC.x==xrand;
//top to bottom object fall-loop--------
}

this.germs.y=yrand;
if (this.germs.y>399) {
this.germs.x==xrand;
this.germs.y==0;
//top to bottom object fall-loop------
}

if (germs.hitTestObject(WCell_MC)) {
//when player hits objects----------------------
germs.x==xrand;
germs.y==0;
score=score+5;
this.dyna.text==""+score;
}

if (RCell_mc.hitTestObject(WCell_MC)) {
//when player hits objects----------------------
RCell_mc.y==0;
RCell_mc.x==xrand;
score=score-3;
this.dyna.text==""+score;
}

if (tasiyot_MC.hitTestObject(WCell_MC)) {
//when player hits objects----------------------
tasiyot_MC.y==0;
tasiyot_MC.x==xrand;
score=score-3;
this.dyna.text==""+score;
}
}

function MoveWCell(event:KeyboardEvent):void {
//MOVE THE WHITE BLOOD CELL START-----------------------------------------
switch (event.keyCode) {
case Keyboard.RIGHT :
//MOVE THE WHITE BLOOD CELL----
WCell_MC.x==WCell_MC.x+5;
break;
case Keyboard.LEFT :
//MOVE THE WHITE BLOOD CELL----
WCell_MC.x==WCell_MC.x-5;
break;
}
if (WCell_MC.x<0) {
//CONSTRICT WHITE CELL TO STAGE-------------------------------------------
WCell_MC.x==0;
}

if (WCell_MC.x>550) {
//CONSTRICT WHITE CELL TO STAGE-------------------------------------------
WCell_MC.x==550;
}
}
}
}
//END---------------------------------------------------------------