No, you can buy it on steam
But if you're a saiko legend or supporter on the server you get it for free, and the Dev gives you a steam key for it
2.1 is the newest version and you need to pay 4$ for it
It won't be free SnS will costs money from now on
I think you need to beat the modes before yangire and Yandere is free
You only need to buy it once
Nope it won't be free on steam will costs around the same as here
You need to pay 4$ to get the 2.1 version