Sorry to hear you're taking it back - hope it's just to get a different ppc, like the touch - or to go to sprint - I surely wouldn't blame you.
There is a Wiki that I followed to reset mine back to stock after I had radio problems. Haven't tried to upgrade my new/replacement one yet.
Here's the link:
http://wiki.xda-developers.com/index...TitanStockHome
It also has links to all the sw/files you need.
Make sure you do a hard reset and clean it off before you take it back. You may need to do the *228 so it will be functional or maybe not if you need an excuse for why you're returning it. GL.