I am also facing that same problem but mine is with the primary arguments.
[unitname,carname,damagename,timename] exec "damagecar.sqs"
_unit=_this select 0;
_car=_this select 1;
_damage=_this select 2;
_timedamage=_this select 3;
if (isNil "_damage") then {_damage=0.1};
if (isNil "_timedamage") then {_timedamage=11};
#loop
if (_timedamage ==0) then {exit};
_car setdammage getdammage _car + _damage;
_timedamage=_timedamage - 1;
~1
goto "loop"
As you can see the above script damages the car within the given time.
The problem is if you left both the damage and timedamage empty in the arguments
e.g [player,jeep1] exec "damagecar.sqs"
An error popped out and says
"_timedamage=_this
error : zero divisor"
(Is there any solutions to this problem?)
Regards,
Haroon1992