When Gary crosses off the tenth pub on the map, the figure of the "modern art" statue can be seen on the map just below the second and third pubs. But since this is the same map he used for the original crawl, before The Network arrived, and since the statue is apparently part of The Network, it should not appear on the map. It is also apparent that the statue was not there at the time of the original Golden Mile since they wonder about what it is when they pass it earlier in the night.
One of the three girls swallows the
wedding ring and later it's retrieved by pulling it out of
her stomach, but earlier in the fight in the toilet when
the boy's head came off, there were no pipes or tubes
connecting the head to the stomach.
Andrew Knightley's law firm is called Beckingham, Davies and Knigthley LLB. In England, the suffix 'LLB' means 'Bachelor of Laws' and describes a person who has an undergraduate degree in Law. Law firms should bear the suffix 'LLP' ('Limited Liability Partnership').
When Gary is telling the boys what he's changed on the car since they last saw it he says "Carburettor" The car is a Ford Granada 2.8i Ghia X this model did not have a carburettor it was fuel injected.
Gary revealing to Peter and the rest of the gang that the car which he bought from Peter in 1989 is still registered to him is unrealistic for multiple reasons. Firstly until 2015 cars in the UK were required to purchase an annual or semi-annual road fund license or tax disc to display in the windscreen. The registered keeper of the vehicle would receive annual reminders through the mail when this was due. This means that Peter would still be receiving these reminders every year despite having sold the car years before. Also, Gary mentions that Peter received penalty points on his license. When a vehicle is caught speeding, a notice of intended prosecution (NIP) is sent to the registered keeper's address showing the location, date and time and details of the offense. With Pete being a senior partner in a car dealership he would certainly know all of this and would likely query why he was still receiving correspondence for a car he had sold on years previously.