Another possibility is my mission, "Dereliction Duty". It's not exactly a murder mystery, but it is an investigation into who is behind attacks on freighters running cargo from Sol to DS9. You have to gather clues to find out who is behind the attacks, but it's probably more of an ST criminal investigation, than a murder mystery. I'm not sure whether it's exactly what you're looking for or not, but you could give it a shot, if you haven't already. Click the banner in my sig for more details.