as title says i used ugx script placer and selected weather fx but as you can se in this pic the fx is played in the sky and the closer i get to the floor, the less the fx gets rendered. it used to be fine, the fx played correctly but suddenly this happened for no apparent reason  can someone help me please?

Just as it is standard in the treyarch weather script the FX is spawned 600 units above the player. I would ensure that the script matches the default output weather script from the script placer. You can try adjusting the height of the spawned FX as well if there's no luck there.