Cinema4D to UE4 - Issues and solutions?

Is anyone else experiencing issues with light maps on C4D objects. Take a look at these screens, although the light build runs ok, the shadows appear very weird on the surfaces, especially with regards to the staircase. One can also see a clear seam along the outer tube. Is this something to do with lightmap texture size?

://i.imgur/rxbLRwi.png

://i.imgur/Ko7SxZR.png

It’s not really what I was expecting out of UE4. :frowning: