When he moved to New York City, he studied screenwriting with Paul Schrader and acting with William Hickey at the Herbert Berghof Studio.
He chronicled his life-changing experience in a book called Mundos sin campanarios ("Worlds without bell towers").
In April 2007 he moved back to his home town Buenos Aires to write two screenplays: La carta ("The letter") and Mujeres de mi familia ("Women of my family").
In 2011 Olguin-Trelawny was Executive Producer of Vidas de película, a TV series produced by the Director's Guild of Argentina (DAC) about in-depth interviews to living film directors from Argentina's golden "60s Generation" like Manuel Antín, José Martínez Suárez, Pino Solanas, Simón Feldman, Octavio Getino, Leonardo Fabio, and Héctor Olivera.
In 2018 he had his first individual show, "El tiempo del árbol" (The Time of the Tree) at Arenales Gallery in Buenos Aires.