The Nexus sites are currently being moved over to their new servers. If you're reading this then you're ON the new server, welcome! The work doesn't finish here though; there's lots of config files, tweaks, module installs and server restarts to go. So hang in there.
The Nexus sites are big sites with lots of specialised code. I'm not a professional coder and I often forget important things, so if the site is breaking then please report it here. Provide the page you're visiting and the error you're getting and I'll get around to it. Your help can speed up the process, thanks.