We tried so hard to make a single inventory slot to work the way we wanted. Sometimes the rig would shoot across the room and would be about 4 feet away as we walked around. In the early builds just bumping into a wall caused the hearts to 'fix' to the walls and made them useless.
Looking at other comments, I feel I failed to describe how to pick up and place the first big heart found in the starting cell and place it in the chest inventory. That heart acted as the health meter and once the soul mate was found was supposed to be touched against it to take you to the credits/ win room. It's looking like that bit may be is not working as intended.
I can't wait to get back in and take all this great feed back to improve the game!
Thanks!