p0tsh0t, sorry about that userID and passcode error. I published a new version yesterday to get rid of the infinite score bug, therefore your old saves may not work. I will try to have a new version out with skip button soon (so you don't have to do the new game again)
About randomly drawing circles, that's actually not a bug. That's because in the beginning there aren't too many different types of zombies, so you can pass easily if you happen to lure all three with your random circles. However, when the games to level 4~5, there will be 4 different types of zombies, then it won't be that easy.
DeNiro, I understand your request for the save/load. With some considerations, I thought the userID and password would be good for exchange among friends. Now I feel kinda sorry that it didn't work out well for you guys and I'll consider using the regular save/load for my future games.