Tony is wearing mostly a 3 line uniform (across his chest). In one sequence though (in the Weapons Center) he is in a 2 line uniform.
On The AB Chrysalis (1976), Maya had transformed into an animal from the planet Kreno that breathes chlorine, which began to "suffocate" when exposed to an oxygen atmosphere. However, here, she becomes the same animal, but has no problem maneuvering within Alpha's normal atmosphere.
After luring the Cloud Monster into the pressure chamber, Tony attempts to buy some time for the door to close by throwing a large air tank at the monster. It catches him square below the belt, just before the door closes, and you can hear David Prowse gasping for breath and muttering "God!" just as it swings shut.
The Alphans are lax as to monitoring the creature's whereabouts, failing to use video surveillance.
It is stated over and over that the aliens want Alpha's life-support system. However, this refers to multiple large-scale banks of equipment. What the creature is actually after is the unit Professor Bergman referred to on Earthbound (1975) as a power converter. This gives evidence that "Earthbound" was one of the eight season one episodes Fred Freiberger had been given (either by Gerry Anderson or ITC's Abe Mandell) to familiarize himself with the series.
It makes no sense for an huge sprawling base to depend on a single piece of equipment for its entire life support system, and have no replacement for it. It also makes no sense that an alien entity or entities require that exact piece of equipment to survive when it can build robots like the one it sent to retrieve that piece of equipment.
Maya is arguably the most powerful person on Alpha. It makes no sense for Tony to restrict her to the Medical Center and, when she goes to help him, tell her to "get out of here!" when she's the only person who can match the creature for strength.
Maya says that Bill Fraser only suffers "bruises and contusions" from a fight with the creature. Contusions *are* bruises.
Sandra is addressed and referred to as "San" by everyone. (Note: Producer Fred Freiberger had renamed Zienia Merton's character "Sahn" after this season's pilot episode).