While there are 14 true Darians, we only see 11 of them: Neman and Kara, the two suited Darians played by Alan Meacham and Michael Boothe, plus the 7 others below.
Thanks to Conrad Turner for identifications.
Tara Faraday (white dress) and Linda Hooks (blue dress; she also works in the Transplant Room). Both returned to the series a few episodes later for guest roles in The Last Enemy.
In lavender, this is Richard Smith encountering the survivors.
In green, this is Sean Hopwood.
In light brown, this is Jeremy Ranchev. The only supporting Darian with a line: "Neman, the survivors have broken in!"
In red, Carl Bohun is stunned by Paul.
By deduction, the Transplant Room Darian here (between Bergman and Koenig) is probably Chris Hodge (imdb, but he looks nothing like the actor in Monty Python, who was also a musician).
The big bearded survivor is Ron Tarr
On the right is Allan Travell.
Stuntman Terry Plummer
On the right, Dan Long
Stuntman Joe Dunne in the foreground here, with Ron Tarr and Bill Hemmings behind.
Stuntman Nick Hobbs (later to play Clive Kander in The Bringers Of Wonder). In the episode he is normally at the side of the frame or in the distance, often out of focus, until the fight with Morrow and Carter.
James Muir in the centre here.
Speculative: there is a "Mel Walker" credited. This might be Michael Walker who guest-starred in Lambda Factor
On the left is Robin Hopwood, on the right Valerie Phillips
On the right, Jenny Cresswell, regularly an Alphan in Year 2
In the centre foreground, Rosalynd Bailey
On the left, this may be "Theo Hayman", who resembles the actress Carole Hayman (imdb)
The next may be "Nina Kitchen", who was an dancer (no imdb)
Others are Jennifer Guy and Jenny Cresswell
Copyright Martin Willey.