Thanks,
I made some test: now the title and the content of the post work. Maybe the problem was that I mapped 2 field with the same content.
I think the problem with the author is that I did not understand that it should be a userID. Now it’s clear and it works, but maybe I don’t need to publish it in the post.
I dont’t want to show the excerpt in front-end, but i think i can have a fixed excerpt common for all posts.
Thanks!