Hey! Thanks so much for playing and for the kind words!
You're definitely right about the button mapping being weird - we've been getting that quite a bit!
Solaxi is only meant to be able to move on the one vertical axis (i.e. up and down) and we felt that normal controls would make it seem like he was moving on the horizontal axis too. Instead, we wanted it to feel like the world was moving underneath him, with him running along it like he's on a treadmill - struggling to keep up!
We definitely could have done more to communicate that better though!