This is a working code

Code:
#include <acknex.h>
#include <default.c>

ENTITY* ball;
ENTITY* ball2;


action action_ball()
{
	VECTOR velocity;
	var magnitude = 0.1;
	while(!key_space){wait(1);} //press space to start the chase!
	while(1)
	{
		vec_diff(velocity, ball2.x, me.x); 
		vec_normalize(velocity, magnitude);
		magnitude +=0.003;
		c_move(me, nullvector, velocity, IGNORE_MAPS);
		wait(1);
	}
}

action action_ball2()
{
	while(!key_space){wait(1);}
	while(1)
	{
		c_move(me,nullvector, vector(10*time_step,0,0),NULL);
		wait(1);
	}
}

function main()
{
	mouse_mode = 1;
	level_load("some_map.wmb");
	wait (2); 
	
 	
 	ball2 = ent_create ("ball.mdl", vector(-100, -200, 0), action_ball2);
 	ball = ent_create ("ball.mdl", vector(100, 100, 0), action_ball);
 	
 	
 	vec_set(camera.x, vector(0,0,600)); 	
 	while(1)
 	{
 		camera.pan -= mouse_force.x * 12 * time_step;
		camera.tilt += mouse_force.y * 8 * time_step;
		wait(1);
 	}	
}