Since there is only one network component available (TCP/IP) the command OP Load Network Component is no longer appropriate and has been removed. The default network component ID for TCP/IP is 29(Mac OS), and 2 (Windows). This means that for any commands which require a network components ID, use 29 (Mac OS) and 2 (Windows).
You would write something like:
netCompID:=29 `under Mac
netCompID:=2 `under Windows
$error:=OP Select 4D Server (netCompID;$ServerName;$ServerID;True)