Once the invisible walls start popping up it's easier to time a jump past (over/under) the turret shot and take the shortcut at the very top rather than jumping down and climbing the invisible walls, past the blades, only to be shot by that same turret that guards the shortcut. This shortcut served me from when the walls appeared right until level 40 and made levels 37,38 and 39 laughable. Good luck!
Easy game. I found numerous glitches though, and I'm talking about the ability to move pieces while the ball attempts to enter the basket; not the variety of possibilities to complete each level.
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 "Hedgehog Launch 2"){kind=icon}
 "Dynamic Systems"){kind=icon}