Note that in order to show the puzzle solution I had to use Admin System to not have to retry and to get some better pics.

In order to start your search for salvation, you will have to activate the main event (Generator on the second floor). Also, I suggest you grab a melee weapon.



After starting, jump down the hole that's left to the generator and turn around. You will see boarded up doors with a big "SALVATION LIES BEYOND" graffiti.



Normally, these boards are unbreakable but after starting the map they become breakable. You will have to break the doors too (this is where the melee weapon comes in handy)

In the room, you will find a key on the table next to a lamp. GRAB IT! After that, zombies will be able to break down the walls of this room, so don't stay there.


When leaving the room look to your right and find another set of doors with "the KEY will set you FREE" graffiti. You will be able to open it now.




Inside you will find one diesel canister. Take it and head to the back of the building. (the next step is right under the balcony with a generator)



Jump over the sandbags and turn right, you will see 4 medkits on your way there. When you reach the yellow generator, pour the diesel into it and head to the other side of the building with big green generators




To the right of the generators there is a control panel. TURN IT ON!


After that the radio across the building will have a red light on it.



Go up the stairs to the second floor and turn left, and head for the generator that is outside.



After turning it on, go back to the radio and call the chopper pilot. He will say that you will need to signal him.

This is where your key comes in again. Head for the Lighthouse and unlock the door. Inside you will find plenty of supplies and a generator with a button. Press the button to activate the Lighthouse and SIT TIGHT!




After about a minute the chopper flies in with a bright light. The pilot will ask you to show yourselves, so step outside.



The pilot will say that he can't land and will call a boat, so you're gonna have to hold out some more.

When you start hearing the boat, head for the dock that's next to the Lighthouse and jump on the boat.


After you step aboard, the boat breaks down. The driver says he will fix it, while you keep the zombies off.


After a few seconds he restarts the boat and you can leave.


If you're fast enough, you can complete this map without even earning a gold medal.


CONGRATULATIONS! YOU FOUND SALVATION