The 60 Minutes report airs at, presumably 8 PM eastern (in early September), based on the rundown clock in the edit room. When her husband and son are watching the show in Dallas (at presumably 7PM, it's dark outside.
Also, when the 60 Minutes executive is watching the evening news reports in his office, presumably a few days later (also presumably at 6:30-7:00 in early-mid September), it's also dark out.
After Bill Burkett's filmed interview, the 60 Minutes team pass round a bag of Lay's potato chips. Throughout the scene this changes position; sometimes it's shown facing the front, and then suddenly it's facing the other way when the scene is shown from a different angle.
During the investigation commission, the argument is that the abbreviation, "OETR" did not exist as an official abbreviation and should be OER..Maples then proves that it does exist. The real argument was that "OETR" did not exist prior to 2004 and could not be on an Air Force document in the 1970s.
Around 58 minutes into the movie, when Mary Mapes searches Google for "CBS Bush Guard", the address bar in the Microsoft Internet Explorer shows "localhost:44500". It means that she was not accessing real Google over the Internet but a server running locally on the computer that displayed web pages stored on the hard disk.
The movie timeline shows June 2004 and Mary Mapes is meeting with Josh Howard and Mary Murphy. She describes Bill White as a "business man" in Houston. Bill White was the MAYOR of Houston. (as of January 2004.)
The list of potential corroborators for the documents includes a Lieutenant Colonel, which is abbreviated on the board as "LT CNL". The proper abbreviation of this rank is "LTC" for officers of the U.S. Army, "LtCol" for the Marine Corps, and "Lt.Col." for the Air Force; the most common abbreviation for colonel is "Col."
The only time Redford, as the dark-haired Rather, has dark hair is when he's talking on the phone on his terrace. For the rest of the movie his hair is his usual blondish color.