Approximately 28 minutes in to "Free For All" Number Six is fighting with a man in a boat. The man is about to hit Number Six with a metal rod he has in his hands. There is a camera cut and the rod disappears from the man's hands. Number Six then pulls the man into the water.
Approximately 30 minutes in to "Free For All" Number Six is in a taxi. He passes a man holding a blue bottle of water as if it were a TV camera.
You can see the water moving around in the bottle. There is a camera cut, then a different man is seen holding a blue stirofoam block made to look like a TV camera.
Near the end of the episode, the Prisoner exits Number 2's Office into a cavern with a straw floor. Here he sees a number of people sitting around a pulsating sphere (or possibly a glowing Rover). The funny thing is that there is only one door to Number Two's office and this is the same door through which he entered. The only logical explanation for this scene would be if the office itself had rotated and lined the door up with another room!
The Rover/Guardian Sphere is shown to somehow create two smaller white spheres to support Nadia when it tows her back to shore.
When Number Six and Nadia get nailed into a box for shipment he is on their right and she is on the left. When they are let out they have changed sides. When they are in the box during shipment the supports for the wall between them are on Number Six's side but when they are let out of the box the supports are on Nadia's side.
The door knocker at Number Two's house changes between visits in 'The Chimes of Big Ben'.
At about sixteen minutes in to "The Chimes Of Big Ben" Number Two gets up to leave a table he is sitting at with Number Six. He exits stage right. From stage right a man in a red and black striped shirt enters and then a camera cut occurs, and the man disappears.
In the scene, where Rover "swallows" the pond-man, you can clearly see that the clothing changes from a white-red striped t-shirt to a pink jacket and the face inside Rover is definitely McGoohan's.
This is because in the original script the 'pond-actor' is not even in the scene. The man in the pink jacket is from the episode "The Schizoid Man", which was later cut out and re-used in the re-edited pilot.
The first time Number Six leaves his apartment in the village there is no "No.6" or "Private" sign by the door. When he returns they are there.
At almost 20 minutes into 'Arrival' you see Rover being released from the top of a building. As he floats downward you can see regular cars parked in the background.