How to create an embeddable swf file

Hello. I'm wanting to learn how to create an embeddable website badge. When you hover over it, an opaque layer appears with the word "join" and is clickable to take you straight to the website. The html says it's an swf file.

Example is HERE.

I have Adobe Flash CS3 but I've never used it before and my attempts to animate the layers and create the html for it have gone nowhere. Can anyone point me to a tutorial to accomplish this task? The tutorials I have found are for completely different things.

Here is the embed code for the badge.

Code:

<embed wmode="opaque" src="http://static.ning.com/socialnetworkmain/widgets/index/swf/badge.swf?v=201008181759" FlashVars="backgroundColor=0x&textColor=0x555555&config=http%3A%2F%2Fvidders.ning.com%2Fmain%2Fbadge%2FshowPlayerConfig%3Fxg_source%3Dbadge%26size%3Dmedium%26username%3D1ma9i7x1ifh0j" width="206" height="174" bgColor="" scale="noscale" allowScriptAccess="always" allowFullScreen="true" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer"> </embed> <a href="http://vidders.ning.com">Visit Vidders</a> 

Thank you for any and all tips!