Get ready for a chapter of going up and down ladders...
When the chapter starts complete the small cutscene and then walk up the ladder. Talk to Thumbo and then collect the nearby map piece.
Place the new map piece at the top, and then rotate the middle tile 180 degrees. Head down the ladder and head south for a cutscene. Head back up the ladder you came down on and talk to the girl. Follow the girls instructions and step on the slab to elevate yourself up.
Head east and pick up the map piece. Attach it to the piece you're on, rotate it left twice, and head down the new ladder. Talk to the girl, then the woman in the room to the left.
Exit the same way you came in and interact with the volcano, you'll see a bird get spooked by the heat and fly in a direction. When it begins to fly in that direction add a (the only available) tile and allow it to fly onto it, be quick and flip that tile around so that the same bird then flies back into the volcano. Repeat this until it falls into the volcano and gets cooked.
Head back down the ladder, pick up the map piece and the cooked bird, head to the woman and give her the bird (you may need to head back up the ladder to flip the map piece to connect the underground sections up - you can't rotate the underground map pieces, they correspond to the over ground pieces). Sit at the table and enjoy your meal (there's a mini game here where you're required to spam
Head back up the ladder. Place the new tile down, and head back down the ladder to be able to access a new location. As mentioned earlier the over ground pieces dictate the underground map, so this new piece will have to be placed to match up with the piece where you ate your meal. I've included screenshots of my playthrough but yours may be slightly different.
Head to this new piece, head up the ladder, and head onto the stone elevator. Talk to the girl, head right and talk to the man.
Head down the ladder pick up the map piece in the left room. Head back up the ladder. Place the new map piece on top of the left tile, rotate twice and head back down the ladder - Same as before you might need to amend the rotation/placement depending on if you've moved any of the other tiles around. Hopefully it makes sense, but if you've not made any changes then the above instructions will work fine.
Enter the new tile piece, head up the ladder. Collect the new map piece, and talk to that (rather annoying) little girl. Place the new map piece to the right of where you are, rotating to fit. Below is how mine looked:
Head to this new area, talk to the man. Head south and head up the ladder you originally entered the cave in. Head north and you should see a rock with water pouring out of it. Head to that and walk up to, and into the water. You should get the message "oops you kicked something loose"
. You'll fall into the pit. Talk to the guy in the location you fall.
Head back up the ladder you came in. Head left and on the stone elevator. Down the ladder. Walk to the opposite end of where you are (past the dining table). Up the ladder, and on the elevator. Head to Trumbo who will give you a key.
Head back up on the stone elevator. Down the ladder. Up the ladder at the other end. Talk to the goat and choose to go to Volcano Crater. Talk to the girl then head down the rope ladder.
Follow the girls instructions:
Tug the rope.
Head to the big wall at the back.
Flip the left switch.
Flip the right switch.
Put your hands on the middle wheel.
Rotate left twice (with
Rotate right three times.
Rotate left twice.
Turn right once.
This should "reboot the system". Head back to the rope to be surrounded by lava. Open up the map and continuously rotate the map piece to create a tornado to shoot you back to the ground.
Head to the tile with the people on it, and move as far away from the volcano as possible. To do this move the volcano piece away from you. You'll know if it's far enough away because it will create an X like new piece:
Exit via the ladder south east of your location.
Once up top before doing anything select the volcano map piece and continuously rotate it to create a 'fire tornado', which will grant you a cut scene and this achievement:
Talk to the goat and select Grand Lobby. Talk to Trumbo who will give you a paper airplane, select the minecart and leave to finish the chapter.