Very interesting concept. I too had too much trouble with the first level. I feel part of this issue is the controls are too floaty for the precision needed. I kept finding I couldn't make the first jump because I hadn't accelerated enough and then I'd sometimes slip off the edge of it because the deceleration wasn't strong enough.
I also wonder if it might be better to have the mirror platforms be a different colour (red for mirror, orange for real) because I wasn't 100% sure at first if the 2nd mirror platform wasn't just the actually last platform being mirrored.
Maybe some of the precision issue could be mitigated by having the "invisible" platforms glow or hum when your character is touching them but that might take away from the concept of the game a bit too much.