If there’s a warning of overlapping UVs, then it’s likely that needs to be checked in the material UVs of the scene. However, try not starting there, as there’s lots of materials and I somehow think it is not all the materials that have overlapping UVs…which is how the scene would become so bright all over, I hypothesize. Instead, try these:
- Check if there’s an Unbound Post Process Volume in the scene. Look for it in the World Outliner, select, and look at the Auto Exposure settings, and other lighting settings for something that is identifiably related to the problem (such as a high intensity of global illumination). Try also to disable the post process’s “Unbound” setting, so it’s not blending with the entire world / scene.
- Check Lightmass Importance Volume location and scale. If it’s smaller than the room in the photos, then it could be causing a problem.
- Check Lightmass settings in World Settings. Post a screenshot of those.
- Is there a skylight, and what is its mobility? Is there a directional light and what is its mobility? what are the settings of either (if only one or the other is in the scene) or both?
- How were UV lightmaps made for the materials and meshes in the scene? generated in Unreal, or in an external program?