At about 15 minutes when Teal'c is communicating with the Odyessy while it is near the black hole, Teal'c s voice is lower pitched supposedly by the time dilation, but the communication back to Teal'c from the Odyessy is also lower pitched and slowed. Because Teal'c is not near the black hole and not affected by the time dilation, his voice received at the Odyessy should be sped up when received, and only then affected by the time dilation in reverse.
Morgan La Fey's "hologram" tells Daniel Jackson that the first human to enter Atlantis after the Ancients evacuated was Dr. Elizabeth Weir. However, in the Stargate: Atlantis pilot, the first person shown stepping foot into Atlantis is Col. Marshall Sumner, with Dr. Weir following a few seconds later.
However the events of the Stargate Atlantis episode Before I Sleep, make it clear that Dr.Weir was indeed the first human to enter Atlantis after the Ancients left.
When Col. Carter is briefing the Atlantis team members regarding the Ori threat in the Milky Way, she says the threat was "here", which is impossible, as the Ori were unaware the Pegasus Galaxy was inhabited, so therefore had no interest in the Pegasus Galaxy.
SG1 intends to connect a stargate in the Pegasus Galaxy with the Super gate in the Milky Way, which they do. They leave it active to keep the Ori from using the Super gate to invade, however this would allow the Wraith to reach the Milky Way, though not in Cruisers or Hive ships. On Stargate Atlantis extreme measures, including destroying the city, were to be used to keep the Wraith from finding Earth, which would be much easier with a permanent gateway into the Milky Way.
At 27:34-27:36, shot over Col. Mitchell's shoulder toward the bow of the ship, the accretion disc visible through the bow windows, there is what appears to be a mouse pointer or other electronic artifact of the green-screen process in the largest window panel.