"Anyone have a theory why I have a second set of screws in the tube. The mirror is held by the set closest to the end. The other set isn't doing anything at the moment."

It is my understanding that they are for repositioning the mirror (move it closer to the focuser)to shorten the focal length for astrophotogrphy use. This would reduce the focal ratio, lessen the exposure times and help the camera setup achieve focus. I'm no expert but I did stay in a Holiday Inn Express. Someone please correct me if i'm incorrect.