It's actually some spoiler about a future map I'm creating, but I made a place where you have to make a dart board roll down a cheeze piece into a "closed" door to make it tumble down . But 2 times out of 3, the contraption don't occur. The door stays upward rather than tumbling down . The whole dream is ready to publish, so it's only that thing that prevents me from publishing.

I made pretty sure that the gravity of the object was set for that ingame. I first tough about a possible size matter, but I made the object enough small compared to the door frame, that it should not be stuck in place. I even tested with gravity inside the editor to make sure that the object falls a little, and so makes sure that it's not stucked there because of its size. The bug happens around 2 times out of 3, so sometimes it works. That's what made me think it's probably a bug.