Well, I've given up for now. It's a fairly complex and sometimes confusing level. I'd say it's very hard as opposed to hard. May I ask, did you play through this level yourself? I cheated a couple of times to see if I could find the double jump power up. I couldn't find it in the level! lol That white and black maze area where you go through to get the high jump is wicked. Also, the blue key....wtf? meaning how the hell do you get to it? Also I could never get to the area underneath the man and the little island with the palm tree. That white block was never open for me.
You can't cheat easily to find the double-jump. ;)
The blue key is guarded by lasers, right? Well, if you could turn the lasers off, you could grab it easy. Hint: The switch is only a screen away.
The white block opens if you get past a certain point. That point is for you to explore and find out.
You can't get past the key-blocks without having a platform. Losing the key provides that platform for you. ;)
EDIT: Fixed the ones you found, except for the first wallswim. Where's that at?
OK, I give up. 2 nights later and none the wiser about getting through the 16 numbered shift screens.
There's actually a secret area that would help there,
It's just a bit before you enter.
I got to the end of the area where grandpa was trying to kill me and hit the switch. Then, on my way out I saved. I died to an explosion in the next room, and now explosions kill me instantly whenever I respawn at the save point.
Also, once the passageway to the underwater maintenance area opens, if you head right from the entrance you will find void screens.
Jump from the first green platform to the second green platform. From there, do a challenging wall jump to the third green platform.
That's nice, although the jump itself to get the umbrella is also going to be challenging, but I'd like to figure that bit out myself...
Look in the area around the save point before all the lasers. The room there will give you a very helpful hint.
I did find one minor glitch, though I'm not sure if you've addressed it between my download and when I actually got around to playing it.
During the final "battle", hitting the last warp before the switch got me into a wallswim just to the left of where I should have been. You can probably just turn off Do Not Quantize and that should fix it, but I didn't verify that.
That aside, it's an excellent level. The plot twists were a very welcome addition and there were some very clever moments.
Great music, good graphics, but some flaws in design.
1) x994y1003 or x995y1003 - there MUST be a save spot there, due to spikes in x994y1002.
2) x1009y1002 - the invisible thing is bad.
5) x993y1015 - auto-save shift would be good here.
3) x996y1012 - wallswim if you go down.
4) x990y1009 - void if you go up.
6) x999y1015 - there are 4 buttons, but only 3 are found. That leaves the impression that the 4th was overlooked. It should be told that only 3 of 4 are scattered.