Also make sure your lightmap UV’s are assigned to the correct channel. By default UE4 will try to generate an additional lightmap UV channel which it will assign for the lightmaps. The option to turn that off is in the Import window.
Also make sure your lightmap UV’s are assigned to the correct channel. By default UE4 will try to generate an additional lightmap UV channel which it will assign for the lightmaps. The option to turn that off is in the Import window.