[Ater my sources]
Marguerite (Rita) Winsor [not Windsor] worked in Bletchley Park, with the codebreakers, later in the forties in Lisbon, at the British Embassy, posing as typist, accordingly with the official list of personnel transmitted to the Portuguese Foreign Office.
She was an agent of MI6 as a Secretary. She provided visas for Ian Fleming, Somerseth Maugham and Malcolm Muggeridge, all from the Secret Service; and Alexander Korda, film director
In Otto John escape to Portugal, after failed attempt to kill Adolph Hitler, she had a relevant role in exfiltrating him. John describe it with fulll detail in his book of memoirs.
She was a friend of Klop Ustinov, also an MI6 agent.
After the war she established a travel agency [see The Times, 6 May 1957]. Nadia Benois, Klop's wife designed a poster for the wall of the bureau
I am conducting a research about her role in the Secret Service during the war. After a close friend of her, she had a house in Algarve (Vila Nova de Cacela, Casa Marguerite, n.º 4). She died there, and funeral was in Sufolfk (UK).