Windows Shares are leveraged by Filr to create Net Folders. It might seem logical, therefore, that the rights settings exposed on the Sharing tab in Windows would affect Filr functionality. That is not the case.
Setting Windows Share rights on a Windows Share has no effect on Filr. This is in keeping with the best practice recommendation from Microsoft that Share rights not be used to grant or control file access.
Remember, Filr Sharing is only enabled through the Net Folder proxy user and the file system privileges assigned to it.