I played it for about 20 minutes..
all the art and animation is super polished, so it's hard not to treat it like a finished game... usually at this stage there's mostly temp art!
anyways.. I really love the game, seems really great. I got excellent performance on my modest desktop AMD 4GB ram, 2GB gpu. But I wasn't able to see the game fullscreen, currently it's tiny..so I think that will be a different test when you are able to play it at fullscreen.
for having a healthbar it seems you have a lot of insta-death situations: hopping on the floating bubbles, falling too far, floor flame and pits (although the last one makes more sense).
I also didn't think the elevator controls weren't intuitive.. it took me a sec to realize I had to push down to descend. too bad you don't have an "action" button.
it would be great if you implemented a "look" feature with the right analog stick, allowing you to move the camera down a little and see whats below you (an endless pit or a platform).
I didn't get that far, I died too many times. I can try again though this weekend.
good job so far..