This answer your question: for Windows, a single workstation is a part of a LAN with an unplugged cable!
I think everything is ok in your settings…
You can try, if you have just one computer in your ‘network’, it should not have any harmfull effect. Anyway, if ZoneAlarm start to ask you for accesss rights with frequency, you can turn back to Medium level.
If you do not have connections problems, let’s go and do not worry to much about the ashServ.exe…