I really like the idea of dodging shadows and the atmosphere of your world, but there were a couple of gameplay things that held it back, in my opinion:
Some sort checkpointing would be hugely appreciated. I'm not saying you can't make the player go back to the start, but maybe let them keep the objectives they have gotten already?
The shadows were too erratic. The only good option was to avoid shadow areas completely. I think you could have some fun timing challenges and pattern observation if the shadows moved more consistently.
Otherwise, this is great :)