Chapter 6 - Begins at 38:28
in the video below.
Head forward and an opaque walkway will appear before you. Cross to the left side into the room with white globes on the floor. Stand over the center one and jump to complete the puzzle. Leave and go straight across to the far side, and simply stare at the sundial for ~25 seconds to complete this puzzle.
Go back and take a right across the magical bridge. When you reach the tall tower, push the button to flip it, showing a III in the doorway. Head in and you'll find two pressure-plate puzzles, one on each side. You need to make the floor of each side match the wall on the far side's room to complete them. Just step on/off the tiles to switch them from white to black. To see this in action, check timestamp 41:00 in the video.
Head out and hit the button to rotate the III tower again. On the far side is probably the trickiest puzzle in the game. You'll find a small room with a pillar in the middle that has a vase on top and multiple buttons on it. We shall number them clockwise from the one closest to the door you enter from originally. Remember this, because we will always use this orientation for the numbers, so this numbering is always in relation to how you FIRST inter the room with the button pillar.
So from where you first enter, the button closest to the door you came from is #1. The button 90 degrees to the left (the next one when going clockwise around the pillar) is number 2. The one on the far side is number 3, and the one to the right is number 4.
Press number 1 followed by number 2. Then press number 1 a few times (or number 3 one time) to rotate the door so that you can walk through it. In this area there will be several clear globes, one of which has a blue flame you must drag back to the button pillar room.
*Painting Alert - First though, drop off the side of the 'rolling bridge' and walk toward it to spin it away, revealing a staircase going down. This is where you'll come to start and finish the 5 painting sequence. Head down the stairs and hide behind the far bench to the right so that none of the 4 eyes can see you. This will open the door. Quickly walk out from behind the bench and through the door. The next room has both painting I and painting V. Painting I is above the door from which you entered, and painting V is above the far side. Go ahead and turn around facing back the way you came and pan your camera up to view painting I. It should turn dark when you look at it. Be careful not to look back at painting V before you leave.*
Head back to the spinning bridge and up the stairs to the side. Cross over it and head up to where the blue flame is. You must look 'through' a nearby clear globe so that you're viewing the globe holding the flame through the lens of a different clear globe in order to 'pull' the flame to the globe you're near. Continue to do this, pulling the flame from globe to globe until its across the bridge and in the globe below the platform in the button pillar room.
Push the buttons in this order: 4, 4, 1, 1 (again keeping in mind their location is relative to how you first entered earlier, not to where the door currently is). This opens the path to the 'final' orb. Pull the flame to this orb in the same way, then look at the blue eye that comes out of the opening above and follow its movement until it lands above the far door on the other side of the button pillar room.
Head back into that room and push the buttons in this order: 2, 1, 4. This will align the door with the exit. Head through and onto the dais to finish this final chapter and unlock My Perspective.