No clue what to do

[Ashtoreth]

Did you get the chemicals in the wine cellar? If so, then go to the laboratory and combine them all at the mixing station. Turn the valves and use the chemical container to mix them all. After that, use the mixture on the shadow residue at the entrance to the refinery. Then you're ready for the net level!

He created another thread at the time, as stated in the original post, and the issue has been solved already:

https://www.frictionalgames.com/forum/thread-25524.html