Thank you very much for your reply David, the script is really powerful, unfortunately it doesn’t completely solve the problem because I have to export the open files in one book with the interactive index.
I would need a script that makes me choose which layers to activate among all the open documents.
Currently, to create the books I have to do this procedure: activate only the Italian layer and create the index IT, activate the English layer and create the index EN and finally activate Italian English and images layer to export the book as a high print quality PDF with interactive index. The problem is that I have 12 files open and I have to repeat the operation for other languages, this is really frustrating because I know that if I were able to write a script I would solve the problem.
Thanks again for the support, I’m still very happy to have discovered Page Exporter Utility!