Another part of the Versace legacy began taking shape last week as filming of a TV movie about the designer’s July slaying in Miami Beach started in Ft. Lauderdale. ““The Versace Murder,’’ produced by Pan Am Pictures, will star Franco Nero as Versace, Stephen Bauer as a dogged FBI agent and young stage actor Shane Perdue as Andrew Cunanan, blamed for killing four other men as well as Versace before shooting himself. Other movies about the tragedy are planned, but this one could be the first to air, early next year.