This modification was made to achieve a greater effect of wet asphalt (together with Road Reflections Fix). With it, during the rain (after a time after the start), small circles and splashes will appear on the ground, just like in previous games in the series. They are almost invisible on the screenshots, it is better to see them live.
In version 1.01, a check was added to see if a player exists in the game world. This is done to prevent crashes. Version 1.0 is no longer supported.