Goofs

The opening narration says the year is 2100, yet dialog indicates the year is only 2000 or 2001.

The main control room set changes to a much smaller, completely different one after the prologue. (The prologue was taken from a first season Space: 1999 episode while the rest of the film was taken from the second season, and during the interval there was a drastic set change).

In the opening they identify the date as 2100 but in the audio they say it's well into the 21st century. If it's 2100 then it should be the 22nd century as the 21st century date would be 2000 not 2100. They're about a century off.

The number "5" is reversed on the moon buggy in some shots during the final chase.

During a fight on the moon surface, one actor's helmet visor is seen to open.

Some of the aliens at the back of crowd shots of them are clearly 2D flats.

The notice by the Nuclear Monitoring Station's Cemtral Core access door contains some misspellings: In the advent [event] of an emergency press red button on side B of your comlock. The activator in the pannel [panel] on your left will then open to reveal the emergency red handle which operates the escape hatchway apparatus. Turn the handle in either direction, secondary level. Space suits can be found in lockers B1 and C2.