Yeah, the message is the end of the demo, there are secrets in the first two levels though if you want to check that out (you'll notice that the goals within them have black cores).
Rewind was in the older versions too, you probably missed it because the help panel with the controls was there too but people would skip it by mistake since any input would disable it, I fixed it in this version.
I'll be redoing the levels yet again, general consensus seems to be that they aren't as good as before, this is fine since I'm being highly experimental with them and figuring out what the best designs are, I limited the mechanics in the first level to only the blocks but it's a pretty big level which might scare off people, and the following levels don't much of a curve since it's a mix of old and new levels.
As for story... I will think of something.
Thanks for playing!