How to unlock door with key?

[Zypherzemus]

Hmm.. anyone know how to unlock a level door (on one map) with a key from another map?
I'm sure it's possible.

Did you try it? I'm pretty sure it would work as it is. Or check in the main Amnesia game.

Your suggestion from the other thread? I thought about it and came to the conclusion that it might not work (If you say to post that command in the second level before you unlock the door)
Here's how my story is set up.
4 Maps, the first map (hub map) and then the other 3.
There's a key to unlock a door on the hub map, but that specific key for that specific door is in one of the other levels. I don't know if it would work since the door itself is on the hub map
I'll try though. Where should I post it though? the hub map? or the map the key is in?