What a great game.
Seriously, I just beat the first world and this game stunned me with his gameplay.
It's from Braid that I'm searching for a title like this.
If they could fix the framerate issue, this will be one of the most interesting 2012 indie game.

Play to the end and see if you feel the same. Overall, I liked the style, but I felt that some areas got pretty frustrating; there were brightly lit areas that contained the black, making it not entirely obvious where pits are.

I almost finish it (I miss 9 of the special levels you unlock after beating the first 3 world) and yes, the game is too hard, but for bugs thing.
Too many time a "light" break itself without reason for me, ie when it simply touch a wall (not the spike), too many times I fell into void because of bad programming.
Yes, I love hard games, but not hard games due to bad coding.
My sound also went off and I must use a amatorial fix to adjust it.
You can't release a game like this: in puzzlle platformer you must test everything, because fail thanks to bugs is simply horrible.

I don't know what game you are talking but usually I'll say.
Usually I just love Mass 3 with a femshep and reading those "I will kill my self ending".
Any game doesn't have good shit in ending. =)

Strange I never had any of the issues you mentioned. The only issue I had with the game was that sometime I thought I could traverse a dark area only to get stuck on some "invisible" (dark gray) pixels. If you have time it's not an issue, move the light source a little, but if you have to do something complicated requiting precise timing and precise platforming, it's annoying to miss and have to restart from zero because the darkness are not dark enough.

But that's the only issue I had.

Not the light you could move, the light balls.
Sometime I leave them on the ground and they broke :|

they can break, I think, but not by themselves. There are those levels in the circus where you have to break them. I have not experienced these problems, but I have a graphical glitch which do not let me get to the final 9 levels. Very good game until this point, though.

Yes, it was on a circus level :(ùIf they manage to fix all the bugs, this game can be great

Never happened to me, normally they should only broke if you or something else fall on them or if you drop them on spikes. (or shoot them)

Which version are you playing ? I played (and finished) the Humble Bundle version.

I played the DRM-free version... but I really doubt there is any difference between the two.