Well, first of all you should know how the GPS markings are working in normal ARMA. If someone sees a marking or not depends on which CHAT channel you are when you place the marking. Global - Everyone (removed in newer dayz versions) Side - Everyone on the same side (removed in newer dayz versions) Group - only your squad / group (no one in dayz or only squads with xml files) Vehicle - only people in the same vehicle Direct - everyone near you (40m in beta versions) In DayZ you can use group chat to get your markers private. (as far as it should be in norma ArmA) Now the map copy thing. Also that is already possible with other mods in ARMA like ACE. But its a cool idea :)