The Mount folder path information could indicated that you need a new folder, not just choose path. If you click "Add remote" for the first time, there could be an example where you can follow the steps. To decrease the amount of the needed steps to create a remote, I'd suggest prepopulating the mount path with the default names remote-repo-name[/foder]:
In Reunite, it would be good to have a button to ask for access to remote repo.