After working pretty fine with the combination of SU 2017 and LightUp 5.x since the 2018 version update I have a lot of trouble with
Suddenly there are black ghosty elements when a scene is rendered. Elements which are used within the construction seem to jump out a copy to anywhere – in different positions and numbers, changing their appearance by just shifting the view on the screen or rotating the view a little. None of them is shown in the unrendered SketchUp drawing, nothing to see or to select.
Purging, clearing, rearranging of layers, deleting and redrawing of elements – nothing helps. But when the project is saved as SU 2017, reopened and rendered in SU 2017 everything is ok again.