Medilink uses the Borland Database Engine to access a ParadoxSQL database. This is an old and relatively simple file based database, but may be a little different from what you are used to.
Access to the database is via standard file I/O, which means SMB/CIFS plus NetBIOS/WINS for name resolution.
So you should open ports:
UDP 137 and 138
TCP 139 and 445
More info here: http://www.icir.org/gregor/tools/ms-smb-protocols.html