The killed EH returns two arguments, and they are used in the script like this:
_this select 0 : who's dead
_this select 1 : who did it
If you want to pass more variables:
this addEventhandler ["killed",{[_this select 0,_this select 1,yourVariable1,yourVariable2] exec "yourscript.sqs"
Should work...
Here's a couple of examples:
1)
this addeventHandler ["fired",{if (_this select 2 != "throw") then {[(nearestObject [_this select 0, _this select 4]),_this select 0,_this select 1,_this select 3] call htr_dispFire}}]
2)
this addEventHandler ["hit",{[_this select 0,_this select 2,"imHit_1"] exec "planeHit.sqs"}]
Then you call those elements in the script like you would when using a 'regular' array:
1)
_projectile = _this select 0;
_shooter = _this select 1;
_mode = _this select 2;
_vof = _this select 3;
2)
_plane = _this select 0
_damage = _this select 1
_message = _this select 2