Please note that your link is to skettchuppoint.com and not sketchuppoint.com.

To answer your question, it is possible to retrieve an object created in Sketchup.
To do this, go to the Sketchup menu and do :
File / Export / 3D Model
Then select the file type Collada (*.dae)
Save it.

Then under SweetHome3D you import the Collada object as for any other object (Furniture / Import furniture)