I really am in a nice flow. The whole diorama ended up in the oven and after half an hour I took it out and gave the parts a dab of paint. And ta-dah! It doesn't look like rock any more. Especially after I dusted some gypsum powder over the still wet paint it got that powdery snow effect I was hoping for. Even after blowing off residual powder there still remained enough to keep the effect. Even in the crevasse it looks like fresh powdery snow that just caved in. Even the Sno-Cat already looks totally right even though it still lacks its tracks. Now I think I'll call it a day concerning this build.