Some plastic thing that is knife-edged - I used a kitchen scraper tool- will get this open after you remove the screws that are obvious and those under the rubber feet. Two screws were lost from one side of the hinge. Tiny drops of gorilla glue and moving one screw from the other side of the hinge - use glue on both sides of hinge. Gorilla glue is a low-tech tool to give precision hi-tech stuff an extended life - along with duct tape and drywall screws. It's not elegant but it works.