If you're looking for more information about the grass, please check out our Trello board - it contains some screenshots and an animated gif about how snow affects grass: https://trello.com/c/KODxdgZS/140-grass
About a playable demo: We will now finalize our work on vegetation, and there are also a few other, smaller things that need to be done before we can release a playable demo - but it's getting closer and closer.
Stay tuned!