Inground, very old pool with new liner. They replaced some of the liner lock but not all as most in good condition. The pool is oval steel wall that has a few places that has bulged a bit but stable over the years. The liner lock stayed nicely in place all summer but with the recent cold snap, one short piece ( incidentally a new piece with new track) popped out. This is on the curved part of the oval. I'm worried about the winter, under the cover and the potential for the liner to fall out. I will be leaving the pool full of water as we have a very high seasonal water table but I'm wondering if there's some sort of shim I can add to the track to help hold the liner lock in place - tooth pick? Penny/dime? Thin rend of a shim?
