I'm not a Unistorm developer, just one of the users, but I can answer some of these questions. The reason the snow shader is in a different location and is structured differently is because it is a separate plugin developed by larsbertram1; you can download it on its own from the asset store as well. Unistorm just imported it into their project. The reason the default prefab doesn't create rain or thunder anymore is because it starts in month 1, which is January, and has a temperature of 30 or so. In the cold months, you get snow instead of rain or thunder, but only if you have the snow shader set up correctly. The "height limit" on the snow shader is how high in your scene the snow should be, so you can have it only snow on the tops of mountains for example. If this is set too high and you're not standing somewhere high up in your scene, you'll never actually see the snow. If you want to get rain and thunderstorms, set the month to 6 and the temperature to 80. In future versions, I think it would be good to separate things out a little more and not have everything in the one giant if/else block. Each weather type should be an object with settings, and the months and temps could control what the default choices are for weather types, but you should still be able to directly set the scene to any weather type regardless of the month or temp, for those who want to ignore that. Currently, for example, if you try to set it to "butterflies" when the temperature is too low, it just does nothing and leaves the weather in a weird undefined state, which probably isn't what anyone wants.