Blam these pesky bugs! I'm ATM wrestling quite ferociously with one of them in my current game project. It seems that it's no trivial manner to move everything on the screen just right so that it appears that the player is going past everything else instead of vice/versa. This is a fairly standard game programming thing, usually called scrolling. I've never had any trouble with it before, but there is just something about this time that makes the thing more error prone. I may choose to go with SFML's built in 'view' class, but we will see how this pans out.
School is making a killing off me at the same time, so hacking through this bug might be a bit difficult. I'm considering coming back to it later, and starting on some other part of Infiltrator. Perhaps a break will give me a useful new perspective.