Thanks a lot for the feedback! Glad you enjoyed it!
For the controls suggestions, my initial plan was to have support for keyboard-only & gamepad input, but dropped those plans due to lack of time. My intention at the moment is to return to those features once I've rested a bit from the development, though. The WASD input you mentioned in Edit Mode is leftovers from this attempt to support non-mouse input, just left unfinished.
The route shown in the clip is indeed unintended, but in a way I'm glad it works because the game as it is lacks any guideposting so it's probably fairly easy not to know whether a given approach is correct or not. I might try to help with this a bit with later updates. The respawning powerup is definitely a bug, though; whoops.