Hi there, I put this bug report in my review before i realized this forum was here, sorry about that.
In world 5 room 5, if you throw the cube at a certain point, you can accidentally throw it far enough to where it reaches the grass above that is inaccessible without it turning into a white platform. You end up stuck and can't progress any further so you have to die to reset it.
It doesn't take very long to reach that point again so it's not a major bug but I thought i would report it still. I will redo the level to provide a screenshot if I can.
Edit: here is a screenshot:
Edit 2: This same thing can happen in world 5 room 8