Just upgraded one of the sites I run to 2.1.1 and after reinstalling the gallery, I get errors related to $txt['smfgallery_admin'] not being defined (two instances in GalleryHooks.php and one in Gallery2.php) - it should be $txt['gallery_text_adminpanel'] instead.
The odd thing is I just upgraded another forum on the same server last week using the same package and don't have that problem. The one I upgraded last week still says "Gallery Configuration" in the admin center as well instead of "Gallery Administration Panel".