I have had no success attaching the DirectionalLight to the BP_Sky _Sphere. I have tried, with futility, many times to assign the DirectionalLight to the appropriate slot in the Sky Sphere, in the project with which I’m involved. I created a simple test map - same engine version (4.25.4) - and had no difficulty whatsoever attaching the light to the bp. Nor did I have trouble attaching the light in a different sky sphere (Ultimate Dynamic Sky, I believe). So, I’m leaning toward a setting in this project that I need to find and address, that is causing my frustration.