EMBERZONE

Approximate time to 100% is 5 minutes.

Restaurant

After starting the game, turn 180° and walk behind the counter with the 2 sales women, opening the door behind it.
Approach the light switch and flip it 2 times.
(Unlocks "Easter Egg")

Streets

Leave the Restaurant through the glass entrance doors
After the cutscene has played, turn to your left and speak to the woman in the white shirt
(Unlocks "Chatterbox")

Metro

Turn 90° to your left and walk straight forward until reaching the Subway entrance. Now walk down the 3 sets of stairs and take the Metro.
(Unlocks "Home")

Home

After the cutscene has played, enter the kitchen and face the top drawer in the kitchen that is closest to the kitchen window.
Open it and take the dog food, then turn 90° to your right and fill the dogs trough.

Finish the rest of the game, which is straight forward, to unlock the final achievement.
(Unlocks "Final")