As this map contains a lot of different 'seperate puzzle chains' I cant offer a step by step guide. Shown below is the map with the order of rooms opening. You will start in Red 1 / Blue 1 respectively. I will list the main mechanism (last puzzle part) first that will open the respective door. Following the whole puzzle chain starting at the first step of the puzzle.

I recommend playing Shared Effort (first map) before this, since it contains information you wont get explicitly in this map.


Map of room order
https://imgur.com/2E7SRxF


Red 2
Main mechanism:solve the golden ball puzzle at the door
Hint:You need information from the blue side.The blue side has the same kind of golden balls.
Solution:1 full circle, 2 empty circles, 3 empty circles, 4 full circles


Blue 2
Main mechanism: solve the colour cube puzzle in Red 1
Hints:use colour theory to make the equations be correct.
Solution:blue + red = purple, yellow + red = orange, blue + yellow = green


Blue 3
Main mechanism: solve the puzzle above the doors in Blue 2
Hints: There is additional information in one of the wall panels in Red 2. The key can be found in Red 1. The key is above the door in Red 1 (button). Open the wall panel in Red 2 and combine the information you get with the information in Blue2. the colors in the door corners have a numerical value.
Solution: Left door 6, middle (cross) door 7, right door 8.


Red 3
Main mechanism: stepping on both pressure plates
Solution: Step on the pressure plates in Red 1 and Blue 3 at the same time. In Singleplayer you will get a button to open the door when you get access to both pressure plates.


Blue 4
Main mechanism: solving the dice puzzle at the door in Blue 3
Hints: From Red 3 you can watch through the window into the blue side. You are looking to give information about dice.
Solution: 6 - 1 - 1 - 6


Red 4
Main mechanism: solve the domino puzzle in Blue 3
Hints: Theres a locked drawer in Blue 1 that needs an object to open.
Solution: Take the vynil from the shelf in Red 3 to open the drawer in Blue 1. Use the key you get on the other wall panel in Red 2. The first 2 pieces are given by the panel, the other 2 follow the sequence.black 2 | empty, white 3 | 2, black 4 | 4, white 5 | 6.


Red 5
Main mechanism: solve the bookshelf puzzle in Red 4
Hints: The right book combination can be found in the table drawer in Blue 1. You need a hidden hint in Blue 1 AND the information from the colour puzzle in Red 1 to solve it.
Solution: There is a hidden note on the shelf in Blue 1 that says blue = 5. solve the colour cube puzzle in Blue 1 orange = 38, red = 22 (27 - 5), purple = 27. solving this gives you the code for the books: I - III - VI - IX


Red 6
Main mechanism: solve the world map in Red 5
Hints: you will need to solve the black ball puzzle in Blue 3 beforehand. The hint for the ball puzzle is hidden in Red 4. you will need an additional object to solve it.
Solution: find the note for the black ball puzzle in Red 4 between the books on the bookshelf. ball puzzle: top row - middle white, middle row - both white, bottom row - middle white you need the black cube from the closet in Red 1 to put in the middle.With the flags on your map you can solve the puzzle in Red 5. countries shown: Chile, Finland, South Africa, India.


Blue 5
Main mechanism: solve the puzzle with the chips in Red 6
Hints: Use the chips to make a sequence happen (left equals right)
Solution: to get the amount on the right you have to divide the amount on the left by 2 and add 50 to it. top to bottom: 550, 500, 200, 100. The higher amount has to be used first!


Blue 6
Main mechanism: aim a lightsource at the mirror in Blue 6
Hints: you can see the mirror from Red 6 through the window.
Solution: use the light tower in Red 2.one button moves it to Red 6, one makes it rise, the light has to stay on, turn the light towards the mirror.


Blue 7
Main mechanism: solve the lid puzzle in Red 3
Hints: you need to solve the lid puzzle in Blue 6 first. For this you need the information from the lids in Red 3, check the ceiling.
Solution: solve the lids in Blue 6 left to right: monkey, bird, human, dog. us the information you get to turn the lids in Red 3 in the right direction: dog and bird face towards you, monkey to the left, human to the right.


Red 7
Main mechanism: Enter the date of death in the combination lock
Hints: the correct date can be found in Blue 7
Solution: The date is on the back of the picture frame - 1903


Spawn red exit door
Main mechanism: solve the boardgame in Red 7
Hints: you will have to solve the box with the combination lock above the coloured figurines. The code can be found in Blue 4. The key you get from this is used on the wall panel in Blue 2.
To get the missing 1 blue figurine you need to
1) complete the ritual in B5
+ 2) solve the crystal ball puzzle in Red 7
+ 3) the chess board puzzle in Blue 4
+ 4) the eyeball box in Blue 1

Solutions:
- 1) To open up the crystal ball puzzle you need to complete the ritual in Blue 5. A hidden note in Blue 4 tells you how to do this: use the golden goblet and an item made of gold: the gold bar in Red 6. This gives you additional information on what to do with the demon sigil code you found: count the letters of the demon names on the paintings in Red 2. correct code: 6 - 5 - 4 - 6 - 5 - 7
- 2) To solve the crystal ball puzzle you need information from Blue 5. You can find 3 hints on the crystal ball in Blue 5. the corrects numbers are: II - V - VI (press the remaining numbers inwards). this gives you the last chess piece for the puzzle in Red 7.
- 3) Look for any reference on where to put the chess pieces you can find on the table. put them on the chess board like shown in the painting, be careful to do this from the right side - use already placed pieces as reference. the last piece can be found in the blue lid chest in Red 2. use the information in Blue 2 to solve the shelf puzzle put 2 plants on the shelf below the chest. Use the information you get to place the chess pieces in the right spot in Red 6. This gives you the order of the eyes for the code: green - blue - pink - blue.
- 4) the eyes around the map are attached to a numerical value. green = 2, blue = 7, pink = 4. code for the box: 2 - 7 - 4 - 7.
Now put all the pieces in the right place on the board and the door will activate.


Spawn blue exit door
Main mechanism: solve the crystal lock in Blue 7
Hints: to open the crystal box in Blue 7 you need to
1) solve the toy puzzle in Red 5
+ 2) solve the colour math puzzle in Red 6
+ 3) solve the letter puzzle in Blue 2.
For the code you need to 4) solve the skeleton puzzle in Blue 7

Solutions:
- 1) put the correct items on the white cabinets as shown on the picture above. to show the middle picture you need to press the lamp button in Blue 4. correct items: globe (Red 4), owl (Blue 5), rocket (Red 5).This lifts up the correct cube pieces in the cabinet.
- 2) solve the colour math puzzle as before, values stayed the same.correct code:5 - 21 - 16
- 3) put in the correct letters as the code from 1) said. some letters only exist in the toy crate in Red 5.correct code:A - C - F - B - D - H
- 4) put a yellow and a red eye into the correct eye socket of the skeleton. The eyes can be found in Blue 5. The code you get is mirrored upside down. correct code:9 - 6 - 6 - 1 - 2


EXIT
Main mechanism: finish the rest of the map
Solution: In multiplayer both players need to stand on a pressure plate. In singleplayer you will get a button to end the map if both map sides are completed.