I port the laser script found in User Contribution to lite-c, but I always got E1515 in particle routine.
Code:

---

function laser_top()
{
	VECTOR temp; vec_zero(temp);
	my.pan=you.pan;	
	set(my,PASSABLE);
	var shooting=0;
	VECTOR mytarget;
	var rotation_radius = 1500;	
	while (1) 
	{
		my.pan=90;
		my.tilt=-30;
		shooting=0;			
		my.skill1 += 20 * time_step;
		temp.x = my.x - rotation_radius * cos(my.skill1);
		temp.y = my.y - rotation_radius * sin(my.skill1);
		//temp.z = my.z   - rotation_radius * sin(my.skill1);
		c_trace(my.x, temp, IGNORE_ME|IGNORE_PASSABLE);
		if (result != 0) // the player has hit something
		{
			if (you != NULL)
			{		
				if((you != NULL)&&(you.skill11==2))
				{	
					while((you != NULL)&&(you.healthpoints>0))
					{	
						mytarget.x=you.x;	
						mytarget.y=you.y;	
						mytarget.z=you.z;		
						vec_set (temp.x,mytarget.x);
						vec_sub (temp.x, my.x);
						vec_to_angle (my.pan, temp);
						if(shooting<=0)
						{
							snd_play(laser_wav,50,NULL);	
							vec_for_vertex(temp,my,38);	
							ent_create(lsrbolt_mdl,temp,laser_bolt);
							shooting=random(20);	
						}
						else
						{
							shooting-=1;	
						}
						wait(1);	
					}
					wait(10);
					my.tilt=0;	
				}		
			}
		}
		wait (1);
	}		
}


function laser_bolt()
{
	my.skill20=0;
	set(my,TRANSLUCENT);
	set(my,BRIGHT);
	my.alpha=40;
	my.red = 255;
	my.green = 0;
	my.blue = 0;	
	my.lightrange = 100;   
	VECTOR my_vertex;
	VECTOR my_vertex2;		
	var hit_target=0;	
	my.pan=you.pan;
	my.tilt=0;
	my.emask |= (ENABLE_ENTITY);
	my.event=im_gone;
	while ((hit_target==0)&&( my.skill20<100))
	{	
		vec_for_vertex(my_vertex,my,5);
		vec_for_vertex(my_vertex2,my,6);	
		c_trace(my_vertex, my_vertex2, IGNORE_ME|IGNORE_PASSABLE);
		if (result == 0) 
		{
			ent_animate(my, "fire", my.skill20, ANM_CYCLE);
			my.skill20 +=.2 * time_step;	
		}	
		else
		{
			if (you != NULL)
			{	
				//if ((you != NULL)&&(you.skill11==2))
				if (you.skill11==2)
				{
					you.healthpoints-=75;
					vec_scale(normal,10);	
					effect(sparks,100,my_vertex,normal);
				}
			}
			hit_target=1;
		}		
		//wait(1);
	}
	wait(10);
	ent_remove(me);
}

function sparks(PARTICLE *p)
{
	VECTOR temp;
	temp.x = random(20) - 10;
	temp.y = random(20) - 10;
	temp.z = random(20) - 10;
	vec_add(p.vel_x, temp);
	p.alpha = 70 + random(30);
	p.red=255;
	p.blue=0;
	p.green=0;
	p.size = 2;
	my.flags |= (BRIGHT|MOVE);
	p.lifespan = 20;
	my.event = fade_sparks;
}

function fade_sparks(PARTICLE *p)
{
	p.alpha -= 20*time_step;
	if (p.alpha<=0)
	{
		p.lifespan=0;
	}
}

---

If I take out the "PRACTICLE *p" in sparks function, and remove all p. attribute, no error occur.

Code:

---

function sparks()
{
	VECTOR temp;
	temp.x = random(20) - 10;
	temp.y = random(20) - 10;
	temp.z = random(20) - 10;
	//vec_add(p.vel_x, temp);
	//p.alpha = 70 + random(30);
	//p.red=255;
	//p.blue=0;
	//p.green=0;
	//p.size = 2;
	/*my.flare = on;
	my.bright = on;
	my.move = on;*/
	my.flags |= (BRIGHT|MOVE);
	//p.lifespan = 20;
	my.event = fade_sparks;
}

---

Why?