Bin/gpm: Permission denied

I’m using an vps on digitalocean with Ubuntu 14.04 Nginx and PHP-FPM (PHP 5.5.9-1ubuntu4.12 (cli) (built: Aug 13 2015 22:34:42)).
PHP-FPM pool starts with user: www-data and group: www-data and NGINX starts with user: www-data, html-root folder owned to user: ‘someuser’.
I’m was changed owner group for root to www-data, and permissions like in guide, but I can’t use bin/gpm. Sorry for my English and pleas help.

with bin/grav same problems

Ensure the bin/grav and bin/gpm files are executable by the user/group (+x).