Don't worry, two new participants are coming up soon! We are probably going to join the jam in two weeks! Man I'm excited about this, the previous themes were so uniquely random it's probably gonna be a pretty neat challenge to make a game for this jam.
You can manifest yourself again by pressing J when you're not inside any obstacles. And as a spirit, you can go through most obstacles. Including hills. Try moving around as a spirit at different heights.
Try downloading and running it again, I've updated it. The current build fixes a bug on some hardware so it might work for you, and now it should also always show an error message in case it crashes.