Hello, I'm using server Cauldron and plugin MachineGuardReload.
Normal opening of the door, it does not open, but if you use the key Sneak, the door opens quietly.
Carpenter's Block 3.3.0.
Sorry my english.

I'll test it when I get a chance. If you'd like to expedite the process check if it works correctly without Cauldron, first. Then report back.

In fact of the matter without using Cauldron will not protect the area with the plugin WorldGuard.
Doors do not open on protect the area, but if you use key "Sneak", it will open.

Sneaking forces a new block event to take place within this mod's code, and it's probable that whatever hook Cauldron is using is only called during vanilla activation events -- meaning, it won't know that my code is attempting to activate a block, so vanilla/mod permissions kick in.