Please, add a check for php-ctype extenstion. Getting that error without ctype:
[error] 829#0: *27 FastCGI sent in stderr: "PHP message: PHP Fatal error: Call to undefined function ctype_alpha() in /var/lib/nginx/mywebsql/lib/util.php on line 91" while reading response header from upstream, client: 10.0.0.1, server: database, request: "POST /index.php?q=wrkfrm&type=info HTTP/1.1", upstream: "fastcgi://10.0.0.30:9000", host: "database", referrer: "http://database/index.php?q=wrkfrm&type=info"
I got a headache without that check, lost about 1.5 hours to scan logs from all remotes, so I propose to add it to install.php script to avoid it in future.
Without ctype extension I can start MyWebSQL and login. But if I want to switch to another account and press logout button.... magic comes here! It cant finish ajax request because of 500 server error. And then I was able to do nothing with that. All interface hangs and even after hard page reload (with cache cleaning) it can do nothing.