All,
This issue is related to the alias algorythm behaving differently in OS X 10.10 compared to previous OS versions. We were able to correct the new behavior in the next ArchiCAD18 Update which is planned to be released in March.
Until then the recommended workaround is to use "one dummy user login" to access the file server. The SMB/AFP/CIFS connection to the mounted server should be established with ONE and only one login info, and in this case the references and the hotlinks will be fine. In teamwork all users can use their own account this is only important for mounting the server!