The game was bugged, and I couldn't actually play... On opening, i got a flash of a few screens, then shown a death / game over screen without actually playing anything.

Great art! I think it was fun seeing the normally horizontal crumbling surface as a vertical obstacle. I think the jumping needs some work, maybe less start up, to make it feel more responsive. Some of those narrow crumbling platforms were tough and felt a bit unfair so I think maybe a few more milliseconds before the platform drops would make the section less frustrating.