Everything about this game was pitch perfect. The minimalist art, the mechanic, the controls, the sound; I feel like with a bunch more levels, this could easily be a puzzle platformer you'd see on Steam. The raycast shadows were awesome looking, too.
I love that it's kinda like Super Meat Boy, but your ghost serves more of a purpose than just taunting you. I could gush for a while about this mechanic, and I think you've done a decent job exploring it. I'm sure there are a million other ways you could think of using it. Certainly there could be room for enemies or turrets that you could block with your body. Also maybe if there was some way to turn the bodies into moving platforms, I think there's a big possibility space there.
Now that I've gushed for a while, there were a couple things that I think could be improved. The most important is that I think the time limit should go. I know it's for the jam, but I think the difficulty in the game should come from figured out how to use your respawns to get all the orbs and get to the end (maybe even a reward for beating the par number or something). I think having a time limit just kind of muddies the mechanic and makes it more of a blitz than a thoughtful platformer.
Second thing is that the green squares are too small. This wouldn't be an issue if it wasn't for the time limit, but there were a few times where I nearly ran over on time trying to make the block get in the exit.
Anyway, super cool game. Please keep developing it. /novel