1. Setup headless client as you would in Arma2OA beta build 1.63 Beta

(http://www.reddit.com/r/arma/comments/16nl5x/a_quick_n_dirty_guide_to_headless_clients_for/ [^])

2. Add forceHeadlessClient=1; to Class Item# using a text editor such as notepad++

class Item36

{
 side="WEST";
 class Vehicles
 {
  items=1;
  class Item0
  {
   position[]={17090.363,365.23312,-3771.4404};
   azimut=13.3992;
   id=973;
   side="WEST";
   vehicle="BAF_Soldier_Officer_DDPM";
   player="PLAY CDG";
   forceHeadlessClient=1;
   leader=1;
   rank="MAJOR";
   skill=0.2;
   init="this allowdamage false; this setCaptive true;";
   description="Headless Client";
  };
 };
};

Two outcomes:
(a) At any mission save in editor; forceHeadlessClient=1; is deleted from the class Item# rendering var useless
(b) If the mission is compiled into a pbo in such a way that the editor cannot strip forceHeadlessClient=1; (such as modifying mission.sqm, saving in notepad++, then compiling with a pbo utility) AND forceHeadlessClient=1; is present during a search of the compiled pbo to verify existence; upon loading mission with Dedicated Client present, Dedicated Client is not moved to playerslot flagged with forceHeadlessClient=1;.

Resolution:

1. Add functionality in editor to allow forceHeadlessClient=1; var in mission.sqm saves instead of stripping var.

2. Merge functionality from Arma2OA beta build 1.63 Beta or later or code functionality to move Dedicated Client to player slot with var forceHeadlessClient=1;

**Filed as Engine bug due to functionality that impacts multiple categories such as Editor, Server, Etc