There is an itch launcher that you can use for automatic updates, otherwise you simply download when a build comes out.
Thanks for the fast reply, I bought it and I have to say it's really nice. It's quite difficult to find a 3d-game with such good quality, and I'm excited to be able to witness its future development. ^^
I bought the game, downloaded the donation build, but is still the same as preview build. That means I spen 5$ for something that was free?
No you get future builds too, which from now on is out of "preview".
Current build is v0.0.5 which is a mess, but there should be a stable release here soon.
Sorry it's been slow, but the last public release on new years was the first public release 2 years in some cases, months in others.