I would like to help but I have too many projects with Chernarus Server :|

just make it like put a radio active that circle cherno so they wouldnt be able to get out of cherno and put some mines and booby trap and the rules should be the person who will last for 2 mins on the highest building in cherno. no need to thank me lol

You need to create a public variable.

Once a player from the playerarray list has entered the zone, then set the variable true. If the player leaves the zone, set the variable false.

Get the timer to count your desired time and if after that time the variable = true then stop/restart the mission as someone has captured the area.

To stop the timer if someone else enters, you can do this.

When the player enters, if the variable is already true then stop the timer or send a message saying 'The area is now contested'

Start the timer example:

Every 10 seconds, it will check if the hill has a player in it

    _playerinzone = false 

 if(player distance getmarkerpos "hill" < 50 ) then
            {
            _playerinzone = true;
            hint "The hill is now being captured";
            };
    sleep 10;
};

Capturing the hill example:

Every 10 seconds, it will check if the hill is contested

 if(player distance getmarkerpos "hill" < 50 && _playerinzone = true) then
      {
   hint "The hill is now contested";
      };
    sleep 10;
};

These are just examples, I'm not sure if they work but when I get some free time, I'll try and make my own capture the hill version.