Flash Builder not showing desktop Application

While learning Flash Builder, I am testing a simple application that runs in a browser, the code is like so:

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
 
<fx:Script>
<![CDATA[
private function doSomething():void
{
myPanel.visible = false;
}
]]>
</fx:Script>
 
<s:Panel id="myPanel" x="32" y="38" width="445" height="316" title="My Panel">
<s:Label x="206" y="34" text="Label"/>
<s:HSlider x="171" y="121"/>
<s:Button click="doSomething()" x="182" y="198" label="Goodbye"/>
</s:Panel>
</s:Application>
 

When I run the application in a browser if show fine, but when I set the a project up with the settings for Desktop Application I can't getting anything to show up. I have no problems listed in the problems view. Does anybody have some advice on why I don't see a compiled application.Thanks