AS2 clickTag
getURL(_root.clickTag,"_blank");

AS3 clickTag
//Name MovieClip clickBtn
clickBtn.mouseEnabled = true;
clickBtn.buttonMode = true;

function getClickTag():String{
	for (var key:String in root.loaderInfo.parameters)
		if(key=="clickTag")
			return root.loaderInfo.parameters[key];
	return "";
}

clickBtn.addEventListener(MouseEvent.CLICK,function():void {
	navigateToURL(new URLRequest(getClickTag()),"_blank");
});