Lamia: LAH-mee-uh ("ah" as in "cat," or what you say when someone says "boo")
The Marquis de Carabas: de CAH-ruh-bahs (again, "ah" as in "cat")
Fuliginous: Fuh-li-gin-us
Angelus: AN-gel-us
Majorca: May-YOR-ca
Westmoreland: WEST-mor-lund
Vandemar: VAN-de-mar
Priorities: a round "pry-OWHr-i-tees" (no skipping letters or syllabus, but a softer R) for very posh, or if you want to do modern London Estuary (which is softer cockney and what Victoria Beckham speaks it would be a nasal "pry-OWH-Ri-tees" hitting the R a bit harder.
Jennifer Knight's British Podcast (She recommends "Scotland/ Scottish Accents," "Mind the Gap," "Billy Connolly Interview."