Amnesia: The Great Work - FULL RELEASE

[The chaser]

Well, I'm having quite some problems (basically getting stuck). Now

Spoiler below!

I'm in the prison. I've been breaking my head in order to think of something. I'm very sure that I have to do something with that crystalitzed thing, but I don't know what.

What do I have to do?

Apart from this:

In the very first level, when you go to the storage

Spoiler below!

Where the movable stone gate is, if you face from a direction, you can see some map.

Although I really like it by the moment. If possible, make corridors less large, I spend a lot of times walking.