And there will be other demos or now wait for the release of the full version of the game?
I'm not really sure when exactly the second demo will be out. But when I do I'll update the game page.
The price was 3 dollars (at first), which was reasonable for a low poly niche game like this one. But now that I am upgrading the quality of the graphics, I'm thinking of raising the price to 10 dollars maximum. Again I'll update the game page when my decision is final.