Error:
„Concrete cannot parse the PATH_INFO or ORIG_PATH_INFO information provided by your server.“

Solution:

    location / {
      try_files $uri $uri/ /index.php/$request_uri;
    }

	location ~ \.php($|/) {
		set $script $uri;
		if ($uri ~ "^(.+\.php)(/.+)") {
			set $script $1;
		}
		include /etc/nginx/fastcgi_params;
		fastcgi_pass IP:Port;
		#fastcgi_index index.php;
		fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
		fastcgi_param PATH_INFO $fastcgi_script_name;
		fastcgi_param  URI $uri;
		fastcgi_intercept_errors on;
	}

http://blog.walterebert.com/using-prtty-urls-in-concrete5-with-nginx