try just copy this code to your building function:
while(1)
{
MOUSE_POS.X = POINTER.X; MOUSE_POS.Y = POINTER.Y;
temp.x = MOUSE_POS.x;
temp.y = MOUSE_POS.y;
temp.z = 100;
vec_for_screen(temp,CAMERA);
vec_set(my.x, temp);
wait(1);
}
It has to work if works in mine script

if not... try my.pan += mouse_force.x; and we'll see if you have a mouse in your game