is there anyone who done stench maps ?

I've try to do it alone, and with ouglouk but we still stay locked in a great room where we only see our own dead bodies and between 8 and 10 gunners and a helpfull Grenade launcher.

and about angron premonition ?

Hello !

In the room you describe, after you have killed all the stroggoss, you have to go down and activate a switch, then you take a mini elevator to return up and "normally" you can exit the level by the elevator door just after the stairs.

I say normally because when i was exiting i had a kind of bug, the game crashed and i could not go farther than this point (i already had the same bug in the Angron Mod)

Btw i have a question for you : Did you find the railgun somewhere on the way until this point ?
I Found some slugs at the 3rd level's end so i think it's surely hidden somewhere.