In the sequence when Chris Curry is driving to London to meet with the BBC, he is seen nervously chain-smoking at the wheel of his car. The roof-line of the vehicle used for the interior shots is clearly not a Ford Fiesta.
The archive footage used just before Chris is presenting the Acorn Atom to the press in 1980, shows a Commodore 1701 monitor, 2 Amstrad CPC464s and glimpse of a BBC Micro, all of which did not exist in the year where the scene takes place.
Clive Sinclair receives a cheque for 10,000 pounds dated 1st October 1979. Later on, a news-board pronounces Margaret Thatcher as having won the election; which happened in May of the same year.
After receiving the news in 1981 that Newbury had pulled out of the tender to build the BBC Micro, Chris Curry heads to the BBC in London and is seen making the journey in a Ford Fiesta XR2. The registration number of the car is A638MMJ which means the car was not registered until 1983 or 1984.
Towards the end, Sir Clive is driving in his C5 as two trucks pass. The truck with the Compaq logo on the side is shown to have a modern HP logo on its rear. HP and Compaq did not merge until 2002.
After Clive Sinclair storms off in anger that he will only be remembered for "Jet Set f***ing Willy", Nigel Searle tells his colleague "My lad's on level 7". Jet Set Willy (1984) does not have levels - it takes place on a single game map. (And Nigel Searle did not have a "lad.")