Your screenshot shows the issue. You have "Boxes" group selected, but 3D boxes still show up. This tells me one of two things are going on in your system. Either you have 3D Box images marked as a Box - Front, or you have 3D Box image in your Box Front image group. If in the image group priorities you need to remove it (you then pick 3D Boxes from that drop down menu if you want to see them in the grid like your picture shows). If the picture is incorrectly marked as Box - Front you'll want to change it to 3D box in the Edit Game window.