Thank you for the wonderful work! I now have winter scenery!
It wasn't easy to do it as there are a lot of words on explanations. I thought I strip it simply;
1 - Download JSGME package/folder (I got mine from game front com)
2- Take JSGME exe file from this downloaded folder and place it in the x-plane main folder.
3 - Create a folder called MODS in X-plane main directory.
4- Download Winter Scenery Package (folder)
5- Take out the 'WINTER' TITLED folder from Winter_Package_mod folder just downloaded (containing Custom Scenery & Resources).
6- Place this 'WINTER' folder into the MODS folder you created earlier inside the X-Plane main folder.
7- Launch/double click to execute JSGME file then choose MODS then select WINTER to the right!
Mario's description is easy however Winter_Package_mods folder the title makes things confusion if you don't know it. I tried it many times then gave it a thought and then I realized/tried what it is to be. I hope this also helps to those got confused like myself.
Happy Winters!