If I set:
use-player-login-ip: true
I get a 500 internal server error, but nothing is showing in my apache log...
Says its coming from line 9666 of jquery-1.11.0.js:
xhr.send( ( options.hasContent && options.data ) || null );
I get same error if I try to enable login, and register.
If I hide IP, or just let usernames be the ip, works fine.