Okay I cant get it to not spawn at start but I did find another option. Move your start locations at somewhere where nothing is (Make an empty area in your map). Then create a location over the empty area. then make the triggers.Oh and you might want to change the players race from User Selectable to something else.
PlayersDefenders
ConditionsAlways
ActionsCenter View on "Create Civs" for current player
Kill all any unit at "empty space" for current player"
There ya go that should kill the units although they will be there very briefly but it shouldnt be a problem since the players view will be centered at their civ.
QUOTE
Just delete the defult Triggers. Case closed lol
Did you even look at the map? He doesnt have the default triggers in it....