What's up with level 24? The red guy kills you and it's provably not possible to get in with the green guy alone even if the red guy didn't exist.
You can maneuver the red guy mid-move sometimes and in that manner actually get the red guy to the exit, but doing so doesn't finish the stage or do anything really. Note you cannot do the same with the green guy.
So no idea how people are clearing this stage.
I think you have a stage with some unexplained game mechanic here, that once you figure out the trick, is probably not difficult at all, but is all in some bit of arcana. Not a great way to design a stage.
I mean I'm sure it's possible as people have done it, but, how? Using the known rules it's not doable, so there must be an arcane trick.
--edit--
Okay I was wrong. Level 24 is definitely doable even without the red guy (though it is curious you can move the red guy mid-green-guy-move but not the reverse of that). When I was brute-forcing it (trying out every possibility) I must have missed one, and wrongly concluded it wasn't possible.
But my goodness that should have been the last stage. Hardest of all stages. Got through that and the rest was a breeze.