Alice Town Harbour
Talk to Lando.
Talk to souvenir seller.
Talk to fisherman.
Exit town using path to island, next to the bar on left of screen.

Map
Go to La Boca del Diablo.

Smoking Wreckage
You cannot get past the drunken soldier on the right. (not yet)
Look at passenger seat to get toolbox.
Pick up cup. (on the road, next to car)
Look at cup to get compass.
Pull compass to get needle.
Exit right and return to map.

Map
Go to Alice Town Harbour.

Alice Town Harbour
Give needle to fisherman.
Talk to fisherman and ask for sleeping pills.
Return to map.

Map
Go to Smoking Wreckage.

Smoking Wreckage
Use knife with wires. (inside car engine)
Note the large tree next to car.
Use wires to honk and grab drunk soldier's attention.
Hide behind the large tree quickly.
When the soldier is checking his car, walk towards the right.
A canteen that the soldier was drinking from is resting next to the large stone.
Use sleeping pills with the canteen.
The soldier will return and chases you away.
Exit right and return to map.

Map
Go to Smoking Wreckage.

Smoking Wreckage
The drunken soldier is knocked out by the sleeping pills you planted in his drink.
Pick up papers from his shirt pocket.
Exit right (or left) to return to the map screen.

Map
Go to Alice Town Harbour.

Alice Town Harbour
Give digsite papers to souvenir seller in order to reveal digsite location on map.
Exit left to map screen.

Map
Go to La Boca del Diablo.

La Boca del Diablo
Pick up clipboard. (resting on crates to the left of the screen)
Exit right and return to map.

Map
Go to digsite.

Digsite
Walk to tents.

Tents
Enter tent on left.
Pick up document on bed.
Walk to outside.
Enter tent on right.
Pick up pen on table.
Walk to outside.
Enter command tent.
Pick up inkpad stamp on left table.
Walk to outside.
Look at clipboard in inventory.
Note the name. (Oberst Dieter Schultz)
Use fountain pen with transfer form.
Select the last name.
Use inkpad stamp with signed transfer form.
Walk to path between tents.

Booth
Talk to guard.
Choose the second conversation option to avoid fighting by handing him the transfer form.
Use red button on booth to open barrier.
Exit right.

Cliff
Save game.
Use Shelly's homework with carvings, then look at carvings.
Note: There's a bug here which prevents further progress if you look at the carvings first.
Each row of buttons contains five symbols.
Press button five, third row.
Press button one, second row.
Press button four, third row.
Press button two, first row.
Example:
x 4 x x x
2 x x x x
x x x 3 1
A cave will be revealed.
Enter cave to complete the demo, watch the final cutscene and credits.
Congratulations! You have finished the game.

Symbol explanation:
The memoirs in your inventory contains clues about which buttons to press.
Translate the spanish text on the right page of the memoir to find out the order.
The first, third and fourth symbol can be found in Shelly's homework.
The second symbol is shown on the right page of the memoir.