Continuity mistake: When Vargas beams up to the Liberator just ahead of Blake, Gan & Vila, he challenges them when they arrive from the other side of the room - by stepping out of the teleport bay. But they're standing in the teleport bay, and Liberator has only one. So exactly where is Vargas standing?
Revealing mistake: Stock footage of the London's launch from Earth is run in reverse when it lands, supposedly 8 months later, on Cygnus Alpha. What are the odds that a remote penal planet will have a launching pad with configurations, lights, buildings and background terrain all completely identical to the launch stage on Earth?