I just wanted to add that Rift Users can ignore all the weather/cloud files, as the clouds in the Rift are always the same and won't change with this mod.
BUT sweetFX is a must in the Rift - keep in mind that you still will have to adjust some settings in the default-ppfilter! (disable autoexposure, turn down general exposure and contrast,...)
Nevertheless, when used on monitor this is by far my favorite visual mod for AC.
Greetz, Fritz