I export a .FBX from Sketchup, and when I try to generate the lightmap UV’s in Unity, it either becomes unresponsive, or crashes instantly. I used to use the Lightup trial, but that ran out. Is there a way to generate the lightmap UV’s without any problems?
Make sure you check recalculate normals and UV’s on import. That is very strange. I export from sketchup using .fbx and and light map a lot. It works just fine for me.