Nice work!
A few bugs/requests after having a quick play with it on my test site;
- If Can browse the library is set to No for a user group then hide the navbar from them.
- When adding new comments, 10 seems to be the minimum number of characters allowed, irrespective of the setting in ADMIN CP > Settings > Options > Message Posting and Editing Options> Minimum Characters Per Post. If possible, if a user tries to enter a message that is too short then it should say what the minimum length allowed is (rather than just "too short").
- Attempting to edit a comment returns an error of "The comment you have entered is far too short and has been rejected." (regardless of comment length).
- There is no way to delete a comment (unless this is done via the "Edit" link?).
- If you enter a comment it displays the message "Your comment has been posted! It will show up shortly..." which remains there even when the message has already shown up and prevents the user from being able to submit another comment (without refreshing the page).
- Error messages (such as "Our records show that this particular media is already in the media library!") don't have 'Back' buttons, so if a user encounters them there's no way to navigate away from it.
- The "Report Media" feature doesn't seem to work.
- Tagging doesn't follow the minimum value set in ADMIN CP > Settings > Options > Tagging Options > Tag Minimum Length.
They're just a few minor things I found but overall very impressive and thanks for your work

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