You start at a house, planning to pick up gear and then enter a pyramid. The locked doors are unlockable. To pick up items you have to move the aim dot exactly onto them and then press E.

First key: on the small table in the far corner of the upper deck
Second key hint: You have to trigger an event before you can get the key
Second key: After you have triggered the event by entering the room with the radio, the key lies on the floor behind the store counter

Equipment hint 1: Two pieces
Equipment hint 2: In the rooms behind the second locked door
Equipment: Binoculars on a crate, and a box on the floor

Enter the pyramid hint 1: Click the gate after picking up all the equipment
Enter the pyramid hint 2: See that closed trapdoor?
Enter the pyramid: On the right wall is a pulley, press E to use it and open the trapdoor

This is a good time to save the game, if you haven't done so yet.

The first puzzle is easy. Go straight ahead and pull the lever. Hint: Don't stand on the trapdoor

The door to the left from the entrance opens, with another lever at the end of the corridor. This lever opens the remaining door but also activates the spike spitter traps, making it hard to get back to the central room.
Hint: Keep your distance
Solution: Stay in the center of the corridor. This way you are far enough away from the traps and don't activate them
Further help: If you have trouble staying in the center, place your aim dot on the central seam of the floor tiles

Next comes a room where you have to press lots of buttons in cells. Press them all and you should be able to open the final door.
Hint regarding the trapdoors: It's possible to walk on the thin ledge surrounding them. Just keep walking diagonally into the wall to avoid sliding off
Hint regarding the center button: It requires a key to activate
Solution for the center button: The key lies in last cell on the left side, next to the skeleton with the diary page

The corridor with the spike spitters was probably intended as a tutorial for the next section, a maze with lots of spike spitters on the walls and a minotaur (or possibly more than one) chasing you. So here is some more information about the spike spitters: Crouching or running does not keep you safe. Their trigger zone seems to be a cube with them at the center. Enter this cube and you die. This means you can stand next to the trap, at its side, with the spikes seemingly pointing away from you, and it will still kill you. In the upcoming maze it is safest to stay on the other side of the corridor when passing a spike spitter.

Now it is time to enter *dramatic drum beat* The Maze. You should already have an idea about the maze's layout, because:
Hint 1: The game showed it to you
Hint 2: Remember the diary page next to the skeleton that had the button key?
Hints about interpreting the information:
Hint 3: The room at the top is the button room you are just now leaving. The eight cells are clearly marked
Hint 4: Now what could those numbers on the map stand for?
Solution: You have to press four buttons while in the maze. These are their locations, and the order in which you have to press them