No, I had people successfully setup OwnCloud w/ajenti-v. You can check the redirects log at /var/log/nginx/....access.log

Yes, just paste it into Websites > website > Advanced > Custom configuration

Also, from the docs: you can add this as custom configuration for your website:

location ~ ^/(?:\.htaccess|data|config|db_structure\.xml|README){ deny all; }

.htaccess and NGINX are completely unrelated to each other. To forbid access to a directory inside your installation, you could e.g. create a Static Files content entry for the relevant URL with a nonexisting path for it.

I have released a small update. Please let me know if it helps.

Please check the log in /var/log/ajenti. Also: http://support.ajenti.org/topic/507352-troubleshooting/

Which e-mail address are you trying to send mail to? silver@ability.ee?
In this case, server silver@ability.ee fails to verify sender address (which is non-qualified: www-data@li573-117.localdomain)

Currently this is only possible through editing /etc/ajenti/vh.json (websites -> ... -> user) and restarting Ajenti

Is there anything in the stdout log as well? If you didn't previously have a wsgi script in your project, you can create a Django one using django start-project