I did finish, though I wasn't sure if there was an alternative, environmentally-friendly ending :P
The jumps were really fast so the platforming was difficult. Not impossible, just a little frustrating sometimes.
About the jumps, it's my bad ! I sync'ed the movement with... the framerate of the screen !!! I guess you use a 144Hz screen, am I right ? I need to modify that part.
There is an environmental friendly ending. :-D