iBooks Author does not show "Narrow No-Break Spaces"

I use the latest French version of the Yosemite Operating System, iBooks Author and I write in French. In this language some punctuation signs must be preceded with a "Narrow No-Break Space". However this "fine space" shows as a no-width space. It should show as the "Punctuation space" width. This space is not even good because it breaks. I really need the Narrow No-Break Space to be conform with the French typographic rules. Is there any way to adjust its width?