In one very brief shot Captain Blue can be seen with a different hairstyle that is the wrong colour (black).
When Captain Scarlet is in the engineering room he knocks out the engineer but in later shots the engineer isn't anywhere in the room. The same thing happens again in later in the episode when Captain Scarlet knocks out a security guard after escaping from his cell but a few seconds later, when Captain Blue runs past the same area, the unconscious security guard is nowhere to be seen.