Calculating Course Duration - workaround, plus feature request

Here's an easy workaround for those looking to calculate their course duration, for all layers - assuming that there's audio/narration on all slides and layers.

1. With all your audio files in one folder,  select all and view Details Pane.
2. Click see more to see the total length of all selected files.

The feature request for Storyline:

• In Media Library, display total duration for selected audio files.
  
  • Display as Total Duration (sum of duration column)
  • Display as multiple Duration (sum of duration x use count)

This would be more useful than my workaround above, as it would account for audio files that are not in the same folder.