I don't think that Slaughterhouse-Five was successful movie material. In fact, Vonnegut's books mostly I don't feel are movie material.
“By no means do I anticipate screening those who come on to campus... And I have no difficulty if a bishop across the country or some local pastor may say that's not Catholic teaching - that's fine.”
“Nine-tenths of tactics are certain, and taught in books: but the irrational tenth is like the kingfisher flashing across the pool, and that is the test of generals.”