Chopper man
I just experienced the same problem. While pulling on the flap, one of the hinge points came loose. I guess I did not get enough glue into the hole I drilled. What I am going to try is on the flap, cut a small notch on the bottom side of the flap to expose the hinge point, fill that area with 60 minute epoxy, let it cure overnight. Then spackle the area to get it smooth, then use trim coat to cover the area where the notch was cut. The rest of the hinge points are good.
You can print out an instruction sheet from Robart on hinge point installation. In step 4 of their instructions, it says in BOLD print,
"Warning: do not use CA glue to when installing Robart Hinge Points this will make the hinge brittle."