The online 3ds to xaml converter is not available any more.
The converter was running on .Net Framework 2.0 and therefore it was only simulating WPF objects. This meant that the Reader3ds that was used by online converter was very limited.
Please use Viewer3ds application to read 3ds file and convert it to xaml or Ab3d.Reader3ds library to read 3ds file in your application. They provide much better reader engine and support many advanced features.