** Using WeBWorK **

There are multiple institutions successfully running WeBWorK behind a reverse proxy, so it's definitely possible.  I don't know if any of them are using nginx, but it shouldn't be any different.

Here are a few things to check:

• Make sure $server_root_url in site.conf matches the desired address for connecting to the server.  If the proxy is enabled then this should be set to the address of the proxy server.
• Check the apache error logs on your WeBWorK server to see if there are any enlightening error messages there.
• Check the logs on your nginx server to see if it tells you anything.
• Check your browser's error console.

If any of those places give you explicit error messages you can post and see if anyone can further troubleshoot.