That was a sweet, short game! The main character is cute.
I instinctively avoided the cracks, thinking you either fall in them immediately or that you can only walk on them once. I'm not sure if I was really in a hurry to get out of the cave in the end, but I rushed anyway. It was very easy, didn't fall once.
There could have been some music or ambience in the first half, and more sound effects overall. Also, I tried walking down at the beginning, went outside the cave and took the darkness with me.