Ahah. Looking at your art file and looking in your fx folder you appear to be missing the stunning_blow.taret fx file. The Crusader’s Stunning Blow fx comes in two parts. The woosh energy line on the sword is stunning_blow and the gleam of light shining on the target’s head is stunning_blow.target (with the stun halo being separate – you don’t need that one).
What do you mean? The files are there or at least from my point of view.