Okay, elgin, I'm just now getting around to replying to this.
I guess my first question is, why did you initially attempt to get IPv6 stuff working? If you're having a problem connecting to the CSSU repository, I don't think enabling IPv6 was going to fix your underlying issue at all.
However, if you just want help with getting IPv6 working, for starters, you should check if other computers that have IPv6 available by default (just about every desktop/laptop should be), by trying to go to IPv6 sites, like the aforementioned ipv6.google.com, or test it by going to ipv6-test.com
Once you've verified that your network as a whole supports IPv6, we can start working on getting IPv6 set up.