So I set it on fire, burn the living crap out of it and go down the hatch to the next level. I climb down the stairs, fall to the water and than what? I can’t open the door, there is no were to go in the pool?
Swim down, there is another room.
Yes, I’m an idiot 
Atleast you can play there, my game crashes if I load into the zone down the hole after the tentacles : (