This feature was in my todo list for a very long time, but now it's done: uploaders are able to add a cover for their movies!

However, there's a few conditions:

1) Users can add a cover for a movie only if the movie was not in the site before.
2) Administrators can "lock" a cover. Then, only admins could change the cover.

Why did I added these conditions? Well, for some movies, finding a good cover is very difficult. So I don't want someone replace a rare cover by mistake.
Some movies also have alternative covers, and I don't want users to swap covers everyday ;)

If you encounter issues when adding cover, please let me know.

Have fun!