Pretty cool feeling game overall. I like the glowing thing on the cube, it looks nice. The very last section going up the shaft with the laser took me a long time to figure out, I think that area might make a lot of players give up; I think the mechanic of recharging your jump on ceilings could be introduced in a better way, that hallway seemed like a dead end.
This is just a thought, but I think the cube rotating the same way when moving left and right could lead to some interesting puzzle platforming design. It felt a little out of place and a little like an unnecessary annoyance.