you have to download all files from part0 to part 12
OR
one of the torrents, which I didn`t tried.
Cause I downloaded the parts complete and one by one.
With all parts, the mod will work. Well, it worked on me, I have to say correctly.
If you have downloaded ALL parts, you just doubleclick part0, which is a zip-file-type. WinRAR asked me, to locate part1 after a while. I packed them all in one folder, but never the less i have to doubleclick part1. After that WinRAR unpacked all parts correctly.
Then you have to choose, which type of roads you want to install. Coose one type and download them. If you got them, just install them, as opelos told you in the readme of the roadpacket.
Ok, now it should work. Trees, Grass, signs and houses should be snowskinned. Attention: your house in the game may not change color. Doesn´t work on me. don´t know if it is a bug on my installation or a bug of the mod. But i´don´t care but that. Didn´t stay long in front of my houses ;).
OK, if you want to be good now, you can download the repairpatch. But it is not really necessary, I don´t see green fields without that.
And if you want to be best, you download the snowy tires, the tyre chains and the winter day mod.
But they are only bonus, they are not necessary to run the mod.
Good luck & have fun. Hope someone can get use of my horrible english :D