hal9000, please install Java, download the Jar executable version of Sweet Home 3D, and run it with the following command in a cmd window:

Code: Select all

java -Dcom.eteks.sweethome3d.j3d.version=1.5.2 -jar [i]/path/to/[/i]SweetHome3D-5.4.jar

(to get easily the path to [font=courier new]SweetHome3D-5.4.jar[/font], just drag and drop the file in the cmd window).
This will run Sweet Home 3D with an older version of Java 3D. I wonder if it will work better in your case.