If you change permissions within all private shares so Users are only granted read permissions, then it will be possible to prevent them from moving files. However, Users and Shares would need to be created within the WD My Book Live Personal Cloud Storage system as it can not join to a domain or use domain permissions. The “Public” share will be the only one unable to allow read-only settings.
Microsoft SharePoint is a Web application platform developed by Microsoft, and integrated with Microsoft Office. I would recommend confirming with Microsoft the requirements for storing Microsoft Sharepoint data into a network location.