Whoops! Yep, that's what I was missing. I've set that up now. Seems to be working in the app now! Thanks for the screenshot - it was very helpful.
You're welcome :).
I just played the game, really liked the graphics, also very simple and fun concept. However, finding the last few cats took me a tad too long. Maybe you could add some kind of cat-transport mechanic to speed up the cats that have to walk from the other side of the map?