Like everyone else said, this is a great game. The controls are responsive, the gameplay is paced and involves alot of critical thinking. I certainly can't complain!
The only issue i've had is with the "????" puzzle, I'm able to make it into the room, however, when I do, I can't figure out the puzzle. I've made it past the first laser and cannon, but then i just cannot pass that part. I've also tried switching the gravity upon entering the room, and the immediately switching back, but that still didn't help at all.
Overall, a great experience though. I'll be looking foward to further updates and hopefully buying the full game at some point.