The desk lamps seen in the room Coser and Rashel arrive in are from the Main Mission set of 'Space: 1999'
The chess computer Carnell uses is a Chess Challenger 1 from Fidelity Electronics. At the time the series was made, this was an actual top-of-the-line portable dedicated chess computer.
IMIPAK stands for "Induced Molecular Instability Projector and Key".
This was the episode with the lowest chart position on original UK transmission.
Chris Boucher would use the character of Carnell again in a Doctor Who (1963) novel "Corpse-Maker" published by the BBC.