Did you play the tutorial? You have to right click the crate with the food to clone for example a watermelon into your gun than you can shoot it. Without loading it, it does not work.
The ghost dogs work in a similar way to the ghost. When you place them on the map, they repel the sheep from their location. Sadly, we didn´t have time to create more levels in a way that you would actually utilize them. Also, thank you.