_density = if (count _this > 1) then {_this select 1} else {0.07}; if (_density < 0) then {_density = 0.07};
_colorCoef = if (count _this > 2) then {_this select 2} else {1}; if (_colorCoef < 0) then {_density = 1};_colorCoef can be negative causing color array to have negative values.
In addition to the above mentioned issue, the function will never execute this code block or use the fourth parameter.
//--- Newspapers
_result = if (_newspapers && false) then {
_newsParams = [["\A3\Missions_PMC\gnews1.p3d", 1, 0, 1], "", "SpaceObject", 1, 5, [0, 0, 1], _velocity, 1, 1.25, 1, 0.2, [0,1,1,1,0], [[1,1,1,1]], [0.7], 1, 0, "", "", _obj];
_newsRandom = [0, [30, 30, 0], [5, 5, 0], 2, 0.3, [0, 0, 0, 0], 10, 0];
_newsCircle = [0.1, [1, 1, 0]];
_newsInterval = 1;
_times = "#particlesource" createVehicleLocal _pos;
_times setParticleParams _newsParams;
_times setParticleRandom _newsRandom;
_times setParticleCircle _newsCircle;
_times setDropInterval _newsInterval;
_newsParams set [0,["\A3\Missions_PMC\gnews2.p3d", 1, 0, 1]];
_herald = "#particlesource" createVehicleLocal _pos;
_herald setParticleParams _newsParams;
_herald setParticleRandom _newsRandom;
_herald setParticleCircle _newsCircle;
_herald setDropInterval _newsInterval;
_newsParams set [0,["\A3\Missions_PMC\gnews3.p3d", 1, 0, 1]];
_tribune = "#particlesource" createVehicleLocal _pos;
_tribune setParticleParams _newsParams;
_tribune setParticleRandom _newsRandom;
_tribune setParticleCircle _newsCircle;
_tribune setDropInterval _newsInterval;
[_ps,_times,_herald,_tribune]
} else {
[_ps]
};So it might be a good idea to just wrap it in a comment block. Function should then return [_ps].