You are free to try, but once you start publishing screenshots/videos/games which use Shade-C, you have to get a license which is 100€ per seat or 100€ per team per game.
Does that mean me/we have to get a License NOW or when its done?! Dont get me wrong, I love Shade-C and im so much thanksful to you for doing this, but buying a License NOW and having the risk of never receiving a finished product is not reasonable. As soon SHade-C is finished I instantly will get a license.
