Dumb question, but your phone is in developer mode? After you click ok when it tells you to install webosdoctor what happens? The pop up goes away but is Webosquickinstall still open? Or does it even open at all? I'm trying to help, but I'm coming up short
If you can't get it to do anything I'd suggest taking it down to your local store (Not sure your carrier) and see about a replacement. I'm fairly certain you can't actually "brick" a Pre, but getting way too frustrated to deal with it is a possibility