I've been stuck on this Test Chamber for a while now and I don't know how to complete it.
What I've done so far:
- Pressed the button to get a cube
- Put the cube in the laser to point the laser to the circle in the wall
You would think that this is all that is required to open the door, but no. The door doesn't open:
I don't know what else to do. How can I complete Test Chamber 8?