On July 15, 1994, Dexter tells his mother that he won't be able to stay to visit her that evening because he already has plans to attend the premiere of Jurassic Park. The UK premiere of Jurassic Park took place a year to the day earlier, on July 15, 1993.
On 15 July 2000, Dexter and Emma meet again at Colin's wedding in London. Dexter takes Emma outside onto the roof, overlooking St Paul's cathedral. In the background you can see two skyscrapers. One of these is the Heron Tower, which wasn't completed until late 2010, having not even been granted planning approval until mid-2002.
Emma and the other students are seen wearing mortarboards as they graduate in Edinburgh, however these are not worn at graduation at the University of Edinburgh (nor generally other universities in Scotland).
The dress code for graduation at Edinburgh is a dark suit or highland dress with white tie for men, dark suit or dress for women. When they are on their way back to Emma's flat they all have random clothes on under their gowns.