I played up to a bit of level 3. I think for the endless runner genre, it would have been better to have fewer discrete Y levels; the keyboard input didn't feel quite right for all the stepping up and down. Also, IMO endless runners ought to have music to help keep the energy level up.
It's an interesting idea and I like the way you introduced a few different mechanics. Good job!
First of all I think something nice for players would be if you made them easy for them to play your game, putting all the files on a .zip is convenient (making a web version is more convenient but the zip would be fine). I think that the general idea of the game is good good and it's fun to play, however, I think the level design probably needs some changes. It's very frustrating that having two paths to choose, you choose blindly (that's not bad) and the next time you try to choose the path you thought was the right one, it changes automatically (that's not nice). My suggestion on how to improve this would be: either you make the level design fix (no changes between trials) or at least give the chance to the player to see what's coming so with skills the player would be able to choose the best path and keep playing. Besides those things, I believe it's a good idea, if you plan to extend it or release it, hope this helps.