I'm surprised I got it six, like I said - I died..wait, I did step on it, then back off when it looked like you were surrounded - that must have been the difference. But I'm not even sure I took more than one step in..I don't know man, that's all I can think of.
Be more than happy to go through it again though!
EDIT: The other night me and LT.Shaffer played on expert and beat it easily. I know it was set to expert, but we breezed through like it was normal...so this game does have a couple of kinks to work out.