When the game version is stable, I publish a demo. So, the game demo is now available with 12 levels + all langagues + dubbing / voice over. Also You can play the demo and then continue playing in full version (you will receive achievements etc.). You can buy the full version in the demo.
More info here: https://steamcommunity.com/app/1564760/discussions/0/5079478487798175793/
