Building a Featured Gallery component for Gutenberg

I’m building a Featured Gallery component for Gutenberg. As a guide, I’m using the existing Featured Image component from Gutenberg. Basically, instead of storing a single image id, the component stores an array of image ids in a dedicated meta field (of type array) called _featured_gallery.
Apparently, the getting and setting part is working, but I’m unable to show the grid of selected images (the featured-gallery-grid part in the code).
Any ideas? My knowledge of Gutenberg and React is limited, so I’m a bit lost here. Any help would be appreciated.