I have the VK810, can't find instructions anywhere.
I also have no screw, but I got it open by starting on the right side and fitting a flat spudger between the frame and the screen and pressing the tool deeper towards the back. This unlocks the snap. There are 5 of these plastic snaps built into the body of the frame on the long sides and a few along the top and bottom. Once I got the right side slightly separated, I worked on the top, then the bottom (used 2 spudgers, one kept the gap open on the side while I worked the top and bottom), then continued inserting the tool along the left side until all the lock tabs were released. The internals look the same as these pics once I got it open. I need to replace the charger plug and will swap the battery as well while I'm at it.