La chambre verte (1978). The photos on the chapel wall consist of Franois Truffaut's friends and idols, such as Jeanne Moreau, Oskar Werner, Jean Cocteau, Guillaume Apollinaire, Oscar Wilde and Henry James, the author of the story on which the film is based, as well as Maurice Jaubert, whose music is used in the film.

The reason for their disagreement is still unclear to me, but it seems that Truffaut had been presumptuous, both artistically and personally. According to Werner (in Ein Nachklang), Truffaut made public some of their disagreements about the character development of Montag and made it look as if Werner was the unreasonable one. He also cut some scenes from F451 without taking into consideration Werner's opinions. OW was also against the idea of casting Julie Christie as both Linda and Clarisse. (I strongly agree with OW on this one!) That's the story as told by Werner. I could be wrong, but I don't think they ever mended their relationship after that.
Which isn't surprising: OW doesn't seem like the kind of person who would take what he considers to be betrayal lightly.

Often times differences are put aside at times of death. He could have been grieving and at the same time he was doing shows.