I found a BUG.
I imported a cs: source map,
I found the mesh lightmap problem,
The color is not normal after building the lights.
Do you know how to fix this?
Not a bug, but a difference in how Source and UE do lightmapping.
Make sure there's only one directional light in your map, otherwise it'll be overbright.
Also, you might have to adjust lightmap resolutions, depending on your map.
Thanks, do you know how to adjust lightmap resolutions?
You can either set your lightmap resolution higher than the default on the ConfigUEr tab so that it gets applied to everything on import (which might be overkill), or adjust them case-by-case in-editor by selecting the mesh in the level, then going to the details tab. Scroll down to the Lighting section, click overridden and select a new lightmap size.
(If you want to do this automatically, I did another plugin that does that you might want to check out)