So first the good -- the graphics, animations and music are all excellent. The dialogue is funny but I would recommend getting rid of G**D*** if you're aiming for a wider audience.
I also thought the game had failed to load after startup. You could hear the piano music in the background, but the rest was just a black screen:
I finally figured out that pressing Space bar progressed to the game. Was there supposed to be a title screen here or something?
From watching your Youtube playthroughs I remember there being a way to roll through objects, but I couldn't remember if that was an ability you have from the very start or one that you need to acquire in the game. Anyways, it was while I was searching for the "roll" button that I noticed that if I pressed "T" or "Y" I alternated back and forth between these 2 screens:
The boss was able to deal damage, btw. Anyways, I had to reset to get out of that loop.
As far as the actual game goes, I found about 2 nuggets, used the shop to buy +1 HP and found the letter M. The boss fights against the devils were easy and actually quite fun (it did take a time or two though to figure out the punching action).
I got as far as the Big Head boss . . . and that's where I got stuck. Trying to gauge the power needed to lob the burger over the wall was pretty difficult and I never did manage to beat him. A power gauge would make it a little easier, or an outline of the lob trajectory.