We moved the site to the new domain:

comics.commonpress.pl

Also, now every signed user can add content to the site. Link to admin panel:
https://admin.commonpress.pl/admin/

We probably won't be using CAPTCHA as it doesn't give sufficient protection against bots and it bothers users. Our plan for now is to install Sblam! - instead of preventing creating bot accounts we will prevent spam. We already use it on our other sites and we haven't had any problems with bots.