Select "REGIONS" from the same window you use to place 'Doodads.' Make sure that the "new region" box is selected (green) and then drag your mouse on the map where you want to make snow. Then right click the new region listed in the other window and select EDIT REGION. A new window should apear. At the bottom you'll see a drop box with different weather effects. Choose the one with snow and you'll have snow flakes on no time.
I do know this - xenforo dropped the ball by not keeping the vbulletin reputation comments as a feature. The loss of the Reputation comments data when we switched to Xenforo really was the death knell for the site when it came to all the users that left. I know I missed it so much and I got way less interested in the site when that feature was gone and I run the site.
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory