I do software development, it's always like that. You just make something and test it they way you expect it to work, and then an idiot comes by does something you never think off, and boom... bug... And mostly with in the first 10 min that someone else does it.
That's also why you don't find bugs yourself, but have someone else doing that for you. I'm not talking about fixing, I'm talking about finding....
So yes, how good you are, he is only 1 man coding. So the moment thousands of people are playing, they will find something..
Of course this update wasn't much to do, except follow the story...