Well it wasn't the prong that was turning. It was the entire arm that holds both prongs. The screw that fell out somewhere was the one that stopped the rest at a certain point every time.

That's why I religiously check my equipment every couple of weeks. When we don't, it will bite us at the most innoportune times. Simple fix, though.

Yeah Mobow, I'm generally the same way. However, I didn't even realize that there was a screw in this particular spot untilI noticed it was missing. Its on the underside of the rest on the launcher arm. Its actually in an area that is slightly recessed, so it doesnt even sit flush with the arm.