Yeah, looking at some of the first pics I saw the springs which must be on the other side. I figure the first owner had trouble, dismantled the whole thing and then put it back together incorrectly. Like that, the springs will push the sliding latch plate to the closed position.

Make sure the latch plate can slide easily and symmetrically when operating the latch handle. If it binds on one screw and goes skew, it may crack that plastic block when you tighten the handle.