If you want it to happen when someone clicks the checkbox, then you need to add a listener for that event.
var cbListener:Object = new Object();
cbListener.click = function (evt:Object) {
if (cb.selected) {
gotoAndStop(2);
}
}
cb.addEventListener("click", cbListener);
(Note: "cb" and "cbListener" are names that were made up for this example. They could be anything you want to name them)
