Exactly the same issue with importing a .SKP direct into Twinmotion. I also found some components or groups move or change size upon import. Exporting the Sketchup file to a GLB or OBJ has temporary resolved the issue but still very frustrating that you can’t import Sketchup directly anymore.
Even with the import from GLB on occasions some small items appear dark (solid black) but not as bad as a direct import from Sketchup.