1 - 1:18 (from the exploded tree, walk away from the hole to enter a fake wall in the tree ahead)
2 - 3:49 (use the wall)
3 - 3:53 (use the button behind the stone decoration to open the wall)
4 - 4:40 (swim into the fake wall on the pillar in the back-right of the underwater chamber)
5 - 6:01 (walk into the fake wall behind the tree to the right of the altar)