This episode's headline: Trouble in Trinidad; Castro's Crunch; Menacing Mussels; Body Language. The guests include BERNARD ARONSON, Assistant Secretary of State; RAMON GONZALEZ, Former Cuban Official; JACQUELINE TILLMAN, Cuban American Activist; RAMON CERNUDA, Human Rights Activist; CORRESPONDENTS: JENNY RUSSELL; CHARLES KRAUSE. Byline: In New York: ROBERT MacNeil; In Washington: JAMES LEHRER