Hi,
I failed to find anywhere any explanation about the Published flag on add new ARP.
Anyone that know what this options does care to explain?
Thanks in advance 
published entries – a special type of static entry for which the Mikrotik answers ARP requests on behave of another host.
I can’t think of too many practical uses for it.
If you have a PC that is OFF and you wish to use wake on lan, normally you’d have to use it’s MAC address and thus would only be able to wake it when on the same lan. If you try to use the IP, the PC wouldn’t reply to the ARP lookup because the PC is off…
With a published arp entry, you’d be able to use the IP address of the machine you wish to wake since the Mikrotik would respond to the ARP request on behalf of the PC.