Was struggling to run this, but got it to work eventually, (although it ran pretty slow on my laptop because I don't have a graphics card)
I agree with the other comment, with a 3D platformer you absolutely need the shadow below the player to be able to line up jumps. In the latest Mario game, I'm pretty sure they have a separate light source just for Mario's shadow, so they can have nice lighting (not needing to be pointed downwards) and still have the shadow in the right place.
Also, was it intentional that you can just spam the jump button and fly to the top? (I feel like I cheated)
(-Joe)