Vanilla 1 is no longer supported or maintained. If you need a copy, you can get it here
Current version is 2.1.11
, released 12 June.
Webserver behind proxy (OpenURL modification)
I know it's very strange for a webserver to be behind a proxy, but there is a rediculously strict firewall in place at my university where I host Vanilla for my society. All outgoing web traffic must go via their web proxies. It's probably not worth making into a extension, but in case anyone else is in the same situation then you can use this modification
to the OpenURL function in \Framework\Framework.Functions.php