C:\Users\Hans>java -jar C:\Users\Hans\Downloads\FurnitureLibraryEditor-1.18.jar
feb 10, 2016 3:22:42 PM java.util.prefs.WindowsPreferences <init>
WARNING: Could not open/create prefs root node Software\JavaSoft\Prefs at root 0x80000002. Windows RegCreateKeyEx(...) returned error code 5.

@Emmanuel,
Above what happens when I do as you told.
Result: Library Editor starts correctly. THANK YOU !!!

I have changed my *.bat script so that it includes the path to the file.
Result: DOS window opens with same error message as above; Library Editor starts correctly.
EDIT
Indeed, I can import files in the Library Editor.
Problem: ALL imported .zip files are called "Model", even when all file names are different. (= Scopia/Hausmann windows from 3D models page.)
END EDIT

@OK
1
- Extensions are visible for all files. I changed this a few weeks ago, and I re-checked today that I did it the correct way.
2
- If I download your example file, it is shown with the extension .sh3d.
- If I double-click the file, SH3D opens and shows the design.
- improved features? Only improved features in W10 are high blood pressure and bugs.

Hans