Great to get some feed-back! I can assure you that no animals suffered during the game production :)
My idea was to make a mobile game so that's why the space is so confined. The game works on a mobile, at least on mine. A round level would not work on a mobile, but the edge effects could be removed by periodic boundaries. On the other hand it is partly the confined space that gives the illusion of an AI, because there is no AI, it is only pigs repelling each other.
I don't know why the game does not work in Firefox, but I suspect the problem is related to the audio.