There is a warning given by botmanager.
If you can be seen from the PvP zone you can be shot and it is a legal kill if they are in a PvP zone. Good news you can be behind cover on the PvE side and return fire legally. So if you choose to build close to the border you could engage in fence line shootings!
/commands
!commands
And yes as you enter a city/town or near a zone there should be a message you see.
As far as the map goes, just create a game with the same map name if you wan to check it out. You can also enter the seed name in the world preview editor at the main menu to see an overhead view.