Reassembling PVC Door lock

[KevinTheKnight]

First things first, I know what I did was stupid but my curiosity got the better of me. I decided to replace the cylinder lock on my uPVC door. I then decided I wanted to know how the lock mechanism works.

Now, the bottom hook doesn't work and I can't work out how it's meant to be installed.

Is this a "common" locking mechanism/would anyone have a diagram of how it's meant to fit together/be able to explain this so I can avoid trying to get a locksmith/someone out?



I know the part on the right slots into the side of the door. But I can't remember if the hook catches "down" or "up". Its the bottom one on the door.

 

[crank39]

Take the other hook gearbox apart to see, take photos first though