[Error] Blueprint weather behaves differently in editor and gameplay.

Hallo
I am having an issue with the lighting.In the editor mode, my level has good lights and everything and when i move to the gameplay, no lighting is coming. I know some error like missing weather class is coming as i got the project from some other guy and the weather script is missing. Any way I can solve this error ? And if weather class is missing how is it working in editor mode ?

IN EDITOR

IN GAME PLAY