If I didn't look wrong, when you open the lock with a key, the key pins can drop out as there is nothing left of the plug to hold them in place.
Otherwise nice little tutorial!
As a hint, try to find "macro" setting from your camera

You get nicer pictures of small things instead of blurs. And when taking pictures, it doesn't hurt to take like 2-4 pictures of the same thing to ensure that you get at least one good
