Dropping an object on specific location as a condition?

I want to make it so that the player has to click on a key, drag and drop it on top of a door, so that it unlocks it. I was looking for a condition similar to "when dropped on position" or "when dropped on object", but I can't find it. Any ideas on how to make this work?

Currently I have an object for the key and an object for the door, plus the background.

You need two conditions for this: Key on drop AND Key is overlapping door.