THe only thing you unlock is the gallery collecting it through levels as it spawns at random, you don't actually unlock the game over animations (for now, can't say if they will eventually)
What problems you have with the mechanics of the game? maybe I can help you understand better.
As for the gameplay outside of mechanics it is as all FNAF style games are, it is a matter of catching the flow of what you should be doing and of course having luck