Problem:

Some of the main tracks on the editing screen in Petal Clip are displayed in black and are played in black with in the preview window.

Cause:

The original video or image files have been deleted.

Solution:

If the original video or image files have been permanently deleted, you will need to recreate the project. If they have not been permanently deleted, restore the deleted files from the Recently deleted folder in Gallery and continue editing in Petal Clip.