Hi!
Congratulations on making it this far!
Spoiler warning: hint
Try using “adjust flow settings” instead of disabling the coolant. Then read the README.TXT that becomes available.
Spoiler warning: spoiler-ier
There is a README.TXT from the consultant hired to build the cooling system, Mia. It tells you how to sabotage the cooling and why you can’t disable it. There’s more information about why in an e-mail thread titled Re: Re: Incomplete Project.
Spoiler warning: all the spoiler
When ending the game by dropping the coolant, you should get an post credits message, and unlock an achievement that you’ve completed the game, along with a message “Game Completed: True Ending.” You will also unlock information you can use to skip the puzzles if you wanted to try other paths in the game.
I think you may have taken every other path already though. 😁