OK, I'm having some real trouble opening up the machine.

I removed all the five screws (two on the bottom, two under the handle and one behind the battery cover) but it still refuses to open. It seems like something is still holding the back case in place.

If it can help, there's a strange "lock" attached to the bottom left of the machine (as shown in the attached photo) that seems to be glued with the case, but I don't see how that should prevent the case from opening.

Any suggestion?