Hans,
There must be a 3D model of an imported piece of furniture that is wrong.
- Stop Sweet Home 3D,
- Open .eteks/sweethome3d/preferences.xml in your home directory with any text editor,
- Search the line that contains Content315000321816400142.pref,
- In that line note the number after the "furnitureModel#" text,
- Find the line that contains "furnitureName#" followed by the same number, and note down the name of the piece of furniture that caused the problem,
- Close the text editor and send me /home/hans/eteks/sweethome3d/Content315000321816400142.pref if possible so I can test where the problem comes from,
- Open Sweet Home 3D and delete the piece of furniture you found from the catalog.