I haven't played it yet, but watched the entire video.

Nice graphics and good use of color.
I like specially those big metal looking clocks.
Nice key and mushrooms sprites.
I didn't get the relation between the walk tiles or the "skull robots" having a heart.
Is that related with the story ? How ?
Is it related with "Alice in Wonderland" ? Is this the same Rabbit ?
It would be nice to understand.
At first it seems awkward (to me) the fact that the character can go through walls, when jumping.
But that is probably a feature of the engine, and it probably improves game play how current levels are setup.
You even used that feature in some screens, to hide a narrow vertical passage, which was clever use of that feature.
The game looks and works fine, but I believe you still have a few items that you could easily improve.
If you feel up to it, I would propose the following improvements/tips:
- Rabbit movement sprites could be made smoother (more frames?)
i.e. make it move more like a rabbit and if possible make the legs walk. They look more like it's sliding in ice.
Since the rabbit is fast moving, you could try something like beep-beep (road-runner) style running, where you don't actually see the legs, but something that suggests they are moving fast, with a few frames, to give a good sense of rotation.
-Jumping sprite could be changed to look more like jumping, i.e. the legs stretch due to the jump, and only after a while in air, would they retract or shorten. Check some videos on youtube, of people jumping to see what I mean.
TIP: You should also add some movement to the rabbits head while jumping. It seems that only lower body (legs) change when jumping.
NOTE: When it jumps, the sprite currently changes, but it seems odd since legs look compressed the whole time in the air.
A landing sprite, could also help here, to help brake the fall.
- You could replace the "skull robots" in locations where they float around, with something more appropriate, like a bat or something like that.
I believe, it would increase variety and make more sense, but it's a nightmare, so anything goes.

- You could make the Big Spider go up and down, while leaving a trailing silk line, so that it looks it's descending the line, instead of floating. I probably is easy to implement.
- If there is any free memory, try to add some more screens or logic puzzles to increase longevity.
Tip: Use some ZX Graphics editor for PC, like "SevenUp" or similar, since it allows you to add frames and then simulate movement, using left and right cursor keys.
These are just ideas, that popped to my head, while watching the video.
Feel free to completely ignore them, they are just my suggestions
