Great game. I had to skip level 307 because in my version, it simply doesn't work. I resorted to looking at the solution, and it's not what happens on my iPhone 6. In the shown solution, after creating the ghost, you turn away from the transporter, and continue with the astronaut and the ghost. But in fact, on my iPhone at least, when I turn away from the transporter, the ghost disappears. Otherwise, great game, only had to cheat twice (not counting level 307).