Phoebe Green mentions having a "certain youthful indiscretions atop Sir Arthur Conan Doyle's tombstone on a misty night in Windlesham" with Fox Mulder. Sir Arthur Conan Doyle was buried in Windlesham but was reburied in Minstead in 1955.
Phoebe Green states that a "minister of parliament" was killed. There is no such title. Individuals elected to parliament are "members of parliament", usually abbreviates as "MPs". Members of parliament and other individuals who form the government/cabinet and have a department portfolio are called "ministers" (i.e. the prime minister, education minister, justice minister, finance minister, etc.). They are appropriately called "government ministers".
During the hotel fire, Mulder places the palm of his hand directly on the door to check for heat from the fire. The correct way to check for heat at a door is to use the back of your hand, placing it close to the door but never actually touching it, so as not to get burned if the door is hot.
Scully claims Cecil L'Ively is a "documented citizen or Great Britain."
Great Britain is not a country. It is the largest island of the British Isles. L'Ively would have a UK passport as he is British.
Just before Dana Scully phones from Mulder's hotel room to ask about the composite sketch, she looks at her wristwatch which as both analog hands and a digital display. The digital display shows 4:22 but the analog hands show the time as 5 past 5.