This isn't 64x64. See how your fonts are smooth, and there are little gaps between the stairs? There's still plenty of time to fix it, and I think the game will translate perfectly well to the 64x64 resolution, but it isn't that right now.
I worked in a 64x64 viewport in the development tool. Perhaps "sub pixel" is turned on? I will look into it, thank you.Edit: I fixed it!
Glad you got it working at 64x64.
I'm hopeless at it though - can't get past 5 or 6 steps!
Thanks for trying! Hmm... I think I have to explain in game that a double jump can destroy spikes. That may solve your problem :)