Normally you would not save a Gathered project unless you were A: wanting to transfer the entire project to another computer (like a render farm, for example), or B: wanting to move all your scene assets (objects, textures, etc.) into a single folder for some other reason. If you're just saving your scene, there's no reason to do Gather the project.
In any case Project Gathering should not cause a broken network like you show in your screenshot. It could indeed be due to Unicode characters though, particularly if you're running an operating system with the language set to something other than English, where there might be special accented characters in path names for example.
- Oshyan