Tom: The bag has torn those flat rubber seals on mine as well. I’ve had to reattach them a couple of times. The canvas bag on mine seems to be oversized and that’s why it bunches up when operating the slide. I assume you install your styrofoam insert through the outside access. The elbow attached to the grey tank inlet was glued and didn’t swivel. All the flexing was done by the hose from the kitchen drain. I’m considering installing a smaller pipe from the elbow that will fit down into the tank inlet and let that swivel. Attached is not so great picture of the bag hanging down under the slide.