Downloaded the demo... kudos to the artist. The pixel art is top notch IMO. The default control scheme had me struggling with the tutorial area but there is key mapping so that's awesome. Will definitely give this another go asap. Congratz :)
edit:
Played about an hour with Cassie... pretty good writing barring the typos. I'm still having issues with the grapple hook mechanic but that's more user error than game design. Overall the game is pretty solid... it gives me Sonic meets Super Metroid vibes and that's a good thing. Kudos guys!