Fotomagico 3.8.3

I have made a presentation with 71 slides for 9:21 minutes. After adding an audio score of 9:25 minutes, the whole presentation extended to 10:21 minutes, adding 8 blank slides at the end of the presentation…?
I have not been able to find a solution on this very peculiar phenomenon? No reply from Boinx either? Can anyone help me on how to avoid having almost 1 minutes of black screen after the last slide for the music to end? How come a 9:25 audio can become 10:21 on Fotomagico?
Thanks for any advice.

What options do you use for the audio? Usually you can take the right end of the audio and shrink it to your last slide.