On the level that is diagonal up/right from the Well warp room, with the image with a cube piece above a valve, I cannot figure out the solution. You can lower the water level to get to a pivot to move a platform, but it doesn't seem to help much.

2 Answers

Position the platform such that when you raise and drain the water, the floater rests on the platform. Then push it on dry land into place as a stepping stone, and raise the water. You should be able to make the jump to the vines now.

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2

If you do it right, the floating barge will rest on the pivot-able platform, then you can slide it to where you need it.