UJK Router table

I have a UJK Router table and the phenolic inserts are tending to seize up after two or three uses.
When you unlock them, they will not release from the table housing. Has anyone else experienced this problem. I am now going to buy some polyurethane clear sheet and drill the appropriate holes and do away with the phenolic inserts. It is 3mm thick and sits over the existing table and the fence locks it in place.