Several Popcorn FX Effects (ive tested "Dry Ice" and "Cigarette Smoke" so far ) are rendered in an unwanted distance away from a character for example. Even placed in front of the char, the smoke is rendered behind the char. Only when gaining brightness of the effect for a certain extend it starts becoming visible in the right place, but thats way to bright for a proper use.
See forum post: https://forum.reallusion.com/554445/Popcorn-Particle-Opacity-Issue and attached image.

Win10 , GTX1080ti, 32Gb Ram, newest Nvidia drivers

The above seems to happen RANDOMLY. On a new session (image 2, Dry Ice) this did not happen.