Thus I'm guessing it had that special rubber Williams restrictor.
The game is also coded weird. For example, in the planet selection screen, the Scarab can change orientation but will only do so if you go a main direction; if you then turn to a diagonal, it will keep orientation but move in that diagonal direction. This is disorienting, particularly on some of the planets. As well, some of the plants you can only move 4 ways, so all in all it's kind of disorienting. Still a neat game, just a little clunky.