I've been told the USB connector on the UNO is a SLAVE port. I don't know what that means exactly since I use it to send and receive all the time but still don't understand the limitations implied by the fact that it is a SLAVE port. If you want to use a USB for an application I have been told you need to get a USB shield, then you can do whatever you want. I suppose you can try to do it without and see.
Perhaps there's actually an off the shelf implementation/library package/kit that suits my needs. So far though, I haven't found this.
With your experience, writing your own library shouldn't be a problem. I have not tried that yet though I would like to.know how to do that. You should read the posts in the DISPLAYS section of the forum and look for the graphic display related posts, particularly the ones that deal with getting it working from nothing.