Probably my last comment for now, the way the spinner blur works at the moment rather ruins the appearance of all but the simplest spinners.
UPDATE: On a related note, I'm trying to make a motor powered axe, and the bot keeps bouncing into the air. When the blur happened in testing, I eventually realised the game's reading it as a spinner, and doesn't seem to like the floor to enter the area through which the "spinner" would rotate if it went the full circle.