This is a fun game. I wish it had some sort of explanation or tutorial though. Some spelling errors are evident. Another problem is that the enemies seem to be piled up in one location. I have piled up resources but can not get to the level's store to upgrade. I have also found a glitch to get to the next level when you click the menu button. I think that with some improvements this game could reach up to a 4/5 but i'm giving you a 3/5 for now.
yeah, its a bug if you go back too far away.