Actually my spray recently stopped being transparent after a steam update...
When i got a new desktop, last fall when going to school i had nearly the same problem. I was able to import it, but my spray wasn't showing up. I messed around with the type picture files. I got Jpeg and Gif to work. It may also be the way ur graphic settings are with vista.
That you would be able to access through control panel. Some individuals were having this same problem on ZM the other day as well. one of them closed down all his steam apps and CS. restarted his computer, reconnected to steam and rejoined CS to the ZM server. his problem was fixed.
-The enemy of my enemy is my friend-