I have noticed that the "Post comment as guest" is located in the theme, but is it possible to use this as template override? Lots of stuff that I don't need, and I would like to minimize it to the core (since there are no settings in component)

I doesn't help to remove the code in the form.php file, because the guest user are still able to post a comment. This is really weired

Hello Kai Roen

Did you already disable this option in Komento > ACL > [choose the component] > Guest? http://screen.stackideas.com/2015-06-04_1059.png

If you already disable this option and still hit this issue, can you provide us with joomla backend and FTP access so that we can check on this?

Please advise