Barry:

There may or may not be "too much" pressure on your oil
door, but that's not why it failed. Even if you had full
atmospheric pressure on the door, say 15 psi, and a 4" x 4"
opening, that's only 240 lbs. In flight, I'm sure your
loads are MUCH smaller.

But even if there were a 240 lb load, that should not
cause adhesive failure on clean joint with typical dimensions
and the right adhesive. Either the door design, the adhesive,
or the prep for assembly was faulty.

Do you have a photo of the failed components?

-bob