If you need to add more images into your Narrative project (maybe the wedding you were shooting was a two day event and you wanted to ingest your images after each day), you can easily do this from the File menu.
Go to File > Ingest More from Memory Card
(This option also works if you want to ingest more images from a folder on your computer or external drive.)
Select the memory card(s) you'd like to ingest from, or click ADD in the bottom-left corner to choose a folder containing the new images.
Once you've selected the additional images, click INGEST in the bottom-right corner to bring them into your existing project:
That's it! Now your new images will be added seamlessly into your current Narrative project.