Sometimes, wall-jumping with the Cat Sunflower's power will do a regular-height jump instead of the tiny jump it's supposed to. My guess is that if you're lined up exactly right with a 16x16 wall tile, the game will do a regular "jump from ground" jump instead of the "detach from wall" bounce.

By the way, did you remember to put my "add visual indicator on solid tiles that Zombies come out of" comment to your to-do list? I'm not sure you actually did anything regarding making the Zombie-spawning easier to see in dark levels if the player is in front of them.
EDIT: If gore is off, enemies will sometimes play an extra death animation. It's easiest to reproduce by playing as Sugar and running at max speed while jumping on top of a jump-able enemy:





