0.5.2 patch notes:
Course screens now display your previous lap's time for a few seconds on completion
Springs no longer prevent the use of your midair jump for anywhere near as long, and double-jumping while you have upwards spring momentum will maintain a portion of the prior momentum (TL:DR it feels better)
coloured spikes now target the player's hurtbox, as opposed to its hitbox. They should feel a lot more generous.
auto-hides your cursor in fullscreen mode when no menu is open
the box that previously turned the lights off now pulls up a "demo end" screen, the same one at the real end of the demo (course 4). It doesnt say it does this, it just does.
minor reductions to the scaling factor of the upgrades in coruse 2
The traversal section between 3 and 4 now blocks players from skipping it when coming from the left (though, it's still possible if you wall-dash or whatever we're calling that tech)
The death animation when players hit spikes should always be consistent now.