for the decal-shadow use a sprite

ENTITY* player_shadow = { type = "your_shadow_sprite.tga";}

action player()
{
set(my,SHADOW);
my.shadow = player_shadow;
while(1)
{
player_shadow.scale_x = 0.5;
player_shadow.scale_y = player_shadow.scale_x;
wait(1);
}
}