The film's music supervisor was Paul Mertz. It seems highly likely that Arnaz liked his name enough to use it for his neighbors on "I Love Lucy" about a year and a half later.
This was Arnaz's last big screen role prior to debuting as Ricky Ricardo on I Love Lucy. He not only has top billing and performs in several musical numbers, but actually wrote two of them: Holiday in Havana (the film's theme song) and a little ditty called "Arnaz Jam."
Desi Arnaz pronounces Cuba as Quba as Americans say it instead of COuba as Cubans pronounce it.
Lolita (Mary Hatcher) drives a 1949 Lincoln Cosmopolitan convertible; the Havana police drive a 1949 Ford.
Desi Arnaz pronounces Havana the American way with a V as opposed to the Spanish way with a B.