Hi, I can't respond on www.joomlaworks.net/forum/k2-en/45667-why-does-k2-have-it-s-own-acls#154824 with a +1 :) Would be really great to see a sollution to prevent specific ACL to prevent/allow access like default Joomla category acl.

I can't find a K2 JED plugin doing exactly that. Being able to make a new article and prevent specific categories from getting posted in. For instance, all teachers can't be allowed to post an item in an event, but only in the blog category.

I tried to prevent Managers to have access to the K2 Media or any other tab within the component>K2 list...

Is this not possible? How does one setup any ACL with k2? To me without these functions K2 is useless.

You should move all editing to the frontend.
You can restrict categories per K2 user group and you can override the itemform.php file in order to display exactly the data you need to specific user groups.