Maybe do you have a error message in the console of the browser, maybe a script problem with other scripts?
Hello.
No, there are no errors in the console of Chrome. As I said, I am the admin and main user of the blog. Here the AddQuicktag Menu is shown and works correctly. Every other user-role does not show the menu at all. AddQuicktag just works for me as an admin.
I cannot see why, there is also no plugin or similar that hides such functions or something.
Maybe you have change the capabilities on roles? The plugin checks, if the user have the right for edit the post type.