Follow these steps to edit a playlist:
Step 1:
You can access the playlist edit menu from two places:
Press the pencil to the right of the name.

Editing a playlist

Press Edit within the playlist details screen.

Editing a playlist

Step 2:
Here you can change the name of the playlist, or add a description and/or comments (optional).

Editing a playlist

Step 3:
You can select how long (in seconds) each file is displayed by pressing the pencil beside each file.

Editing a playlist

Step 4:
In the last section you can choose the transition effect between files, and the display priority of this playlist.

Editing a playlist

Step 5:
Once you’ve made the desired changes, press Save.