Yeah, I'm occasionally encountering glitches with this too. Sometimes when you climb to the top of a wall and jump off, if you press the d-pad at just the wrong moment you can fall through the floor (it can be difficult to replicate). I can change the maximum height that you can climb so that you don't go too far above the walls, although I'm not sure if that is what really causes the glitch.
Also, sometimes when you get to the top of a wall, you are high enough above it that if you press up and right at the same time, you start walking on top of the platform without having to jump at all. I kind of like this, actually. It didn't really make sense before that a ninja would be able to climb ladders but not actually get to the top of the platform without jumping off. The downside of this is that the levels weren't really designed for this, so sometimes you get to the "top" of the platform, but it's actually just a little bit too low, such that if you walk forwards you fall through the floor.
Edit: With the changes discussed in previous posts already in place, changing x1EC35 to x4D makes it so that Deadpool can't climb as high above the screen.