The platform in the room where you get climb is smaller on very hard, but that and the key jump were the only differences I noticed. Strangely the room with the chasing enemies in the wall was harder than both of those "very hard" additions by a massive amount to me, but I've never been good at evading moving enemies, let alone ones that chase.
It's a fun little level, I liked the other not a level more, only, probably, because of that challenge that gave me a lot of trouble for some reason. The end was confusing to me, like Fubaka mentioned. I tried escaping the box for a long time. I really, really liked the part where you jump on top of the blocks and the chompy-mouthed guys fall down as you go across, it wasn't difficult at all but there was something really fun about that visually and even from a gameplay perspective even though it remains the same as if you took the chompy guys away. It reminds me of running up and down angular paths paths in KS. For some reason doing that just feels good and fun, but it's just going up and down. I didn't really have much to say about this level except for that part really stuck out to me. Something that's fun because of how it feels to do it and the style at which it's done.