As part2 and part6 of the original download of the Snow Mod here at GTAGarage.com are broken, and because the installation of the patch to version 1.1 is rather cumbersome, I've put together a complete package of the Snow Mod, already patched to version 1.1. All that has to be done to install the Snow Mod using this package is overwriting the original files with the included modded ones. The complete download has about 4, 3GB.
Here are the links to all 5 parts:
The files presented here are now actually officially available from GTAGarage, so there should be no more problem with downloading them directly from there. Especially download speeds should be much higher from GTAGarage