I'm stuck:
The blond men died, and we split. Robbins goes one way, and I am by myself. I cought the purple rod, saw the stones combination, and tried it in every door, but it doesn't work. Also, there's aroom with five cristals, 4 lit, 1 not.
What am I supposed to do?

There is a ramp right in front the tunnel where you see to the five cristals. Follow this ramp and you come to a "reactor".

Look down and you see 3 crystals and a magnifiing glass on the ground.

go up and you see a controll panel right before where you looked down.

press the buttons in the following order:

five times purple (left button)
two times yellow (down)
one time red (middle)
one time purple (left)
five times blue (up)
one time red (middle)

leave the console and you see another button on the left side of the console.

Push this button and see...


I hope this is helpfull for you.