Hamilton has a low-poly waterfall I believe (lags a lot less)
onelittlecorner.proboards.com/index.cgi?board=fhdownloads&action=display&thread=6&page=4
For the blizzard I could recommend loading Weather/Snow in Object Maker>>Effect Maker>>Particle, re-sizing the particle and cloning it. Play around with it in Object Maker for a bit before saving it. Make sure you click that
clear button before exiting, otherwise that random snow object will appear randomly in your map