There is no easy way to save a D11.5 DIR as an earlier version. The only way to create a D10 version would be to rebuild it. You can export your images, and copy and paste the scripts from D11.5 to D10 (the content of the cast members rather than the cast members themselves). So, it would be a time consuming switch, depending on the your project.
Thank you very much.
The problem is that I have Xtras like Printomatic and database Xtras that does not work properly in Director 11.5. UNICODE is my problem for spanish charset.
So, I hace decided to change to a older version of Director.