Hello Shaipo,
Using version 4.18, I created a new project, added a few Static Meshes to the level (so that the lighting needed to be built), I then searched “Precompute” in the World Settings and checked it. I attempted to build the lighting after checking the box for “Force No Precomputed Lighting” and received the warnings. However, once I uncheck the box for “Force No Precomputed Lighting,” the lighting builds fine.
If there is something that I am missing or you have any questions, please feel free to ask.
Regards,