Oh, glad you got it working! It should support a wide range of controllers, I've tested Xbox 360, PS4 and a random Razer bluetooth one. I didn't think to try with more than one controller plugged in though, it's only single player. But I don't think it will be too hard to add in support down the road.
Thanks for the feedback on the second level. The first one is really supposed to be beginner friendly, but I've had similar feedback that people get a bit turned off by that and by the planet bit at the start.
It's totally kid friendly too! No swearing or anything like that.