I have the version 4.1 and i have some feedback
The restart button turns blue forever after you restart any level once
You could add a indicator that the orange switch can be used to throw objects
You could add a indicator at the menu that shows your extra collectables and to person now that there IS a secret collectable
You could add a new cutscene at the level where you find the other magnet
Awesome gameeee a lot of Aha moments
Sorry by the english