Glad to see you're continuing your work on this! This is awesome.
I like your take on the theme risk-reward theme with the lava. A little more "juice" when burning from it would be cool (maybe have the screen edges flash red or something).
I think the pacing of the levels is great, and the way you introduce mechanics/buttons isn't intrusive.
I'd love to see improvements with the engine in future jams. It's really amazing what you already have, but, for instance, one thing that I think would make this look that much better is doing some things with lighting. Walls that are close look pretty much the same as ones that are far away and generally the grey is a bit dull. Plus, I think the buttons and lava would look awesome with a glow that contrasts from the rest!
Really awesome stuff - looking forward to seeing more!