It would be a huge help if you’d share the LayOut file. I expect the answer to your question would be simple enough to resolve.
There are two common reasons, though. First, the scene properties have been modified for the viewport in LayOut. This modification overrides the settings for the scene in the SketchUp model Hitting the Reset button in the SketchUp Model panel will return the viewport to using the scene properties.
The other common reason for this is that the SketchUp references for the viewport is not connected to the SketchUp model file you are working on. This can happen if you copy and paste from SketchUp to LayOut. May not be an issue in your case if you’ve already tried relinking to the original SketchUp model.
Again, seeing your LayOut file will make it easy to determine what is causing this for you.
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