Changing your in-game name
Launching the game through steam:
When launching DayZ, launch it through the option of Run DayZ.
Click Parameters, located on the left side of the launcher.
Under Profile Name, enter your desired name, which should be kept PG.
Once finished typing, it will automatically save it for the next time you play.
Launching the game through DZSA:
Select Settings (top right of launcher).
Under Ingame Name, input your desired name, which should be kept PG.
Close the Settings window.