I'd have liked better it if the game's response to movement inputs was a little faster. The character must be obese, since it takes him so long to get up to speed, and he can't run very fast... The odds aren't exactly in the little guy's favour, what with him wandering around in a zombie apocalypse. Good thing he has explosives!
I also came across a bug (or I think it was a bug, anyway) in level 2, where it said there were 3 zombies left, but I could not for the life of me find any of them... It made the unresponsive controls and slow movement speed even more frustrating...