i think the collision is a bit too accurate, i died too fast, before i even know what touch me, maybe you can reduce the collision of the wall by some pixel?
also the gap in level 5 is hell, that one gap after you collect the orb (?). The level is easy and that is the only threat, although it is big enough of a threat that my mouse would move some pixel so that i wouldn't be able to get to level 4, so by mercy, can you make it a bit wider?
GG