Controls:
A and D or arrow left and arrow right to move the spirits.
P to attack with a spirit.
Space to jump with a spirit.
Arrow down to crouch.
Escape to return to the menue.

The game saves automaticaly when entering a new level. You can return to you last checkpoint 
via the load option in the menu.  

If you are stuck or not sure wether you faced a bug, you can watch a full walkthrough via 
this link: https://youtu.be/2Dbj9ep48D8