I did not used Roadkill. SketchUV page show some videos with RoadKill but I think it is to have a better UV mapping. I did not made a lot of tests. I just wanted to share this quick solution. I export my .obj with a .obj exporter from Octane Render because I have the free version of Sketchup. I think you have to pay for Octane to acces to the forum where tou can download the Sketchup exporter. For now, I have no errors with lights.

If you want to solve the problem with UV overlapping when building lights in Unreal Engine, you can download SketchUV from Sketchup Extension Warehouse

I exported .obj from Sketchup and imported it in UE 4.7.1