flash crashes on simulate download

create a recangle shape. convert it to movieclip symbol: object1.

name the instance of object1 "main".

enter the movie clip "main".

create another shape. convert it to button symbol: button1.

name this instance "btn1"

exit the "main" movieclip and go to main timeline. add this AS3 code:

main.btn1.addEventListener(MouseEvent.CLICK, btn1Clicked );

function btn1Clicked(e:Event)

{ this.removeChild( main ); }

----->>> testing:

press cmd+enter.

click btn1. watch everything disapear!

click cmd+enter to simulate download

flash will crash here!!!!

you must re-open flash. this ALWAYS happens. why???