Quaknet has some limitations with kiwiirc unfortunately, and it looks like the efnet server they use for kiwiirc no longer exists. I'll look into getting one of there other servers working again.
You can put kiwiirc wherever it suits you best, but the official installers places the kiwi files in /usr/share/kiwiirc. If you're using nginx then you can reverse proxy to your kiwiirc port, take a look at nginxs proxy_pass config option.
Darren