I am getting a 504 Gateway Time-out error whenever I access a site with an
8080 port which is the same as my HTTP proxy. I thought it was a filter
issue so I had them had the filters down for testing and that allowed me
to access the site with the 8080 port.

Do I have to change my http proxy port to any other than 8080(and ofcourse
the other ones that might be in use)?

filters are used
http proxy is setup as per craig's book.