Its easy to make a sprite face the viewer, it does so automatically. But how
can I do that with a model? If I don't want the mdl to fight or be the player, but just be in the world and rotate to face the player if he walks close to it.
you could have a gun mdl sticking out of a slot, or a gun turret and it would point at you as you went by, for example. Just to look threatening. Dosn't need to actually fire.
Please, do you know a simple action for this?

Use vec_to_angle. There's an example in the manual:
Code:

---

function turn_towards_target()
{
  // get the direction from the entity MY to the entity YOU
  vec_set(temp,your.x); 
  vec_sub(temp,my.x);
  vec_to_angle(my.pan,temp); // now MY looks at YOU
} 

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