This has nothing to do with GeneratePress.
Elementor lightbox doesn’t have the carousel option. OceanWP has its own Lightbox module which is replacing the Elementor lightbox. We won’t be adding a lightbox to the theme, it is definitely plugin territory.
Try this – its been mentioned in the forums before:
Premium Grid for Elementor solved the problem and does not add weight.
But thanks for trying anyway. Really weird that Generatepress does not offer that basic feature for photo galleries.
Glad you found a solution.
As i said lightboxes are plugin territory – not everyone needs or already has the function through another plugin. Adding one to the theme would mean a high chance of the code being redundant, which would just add bloat to the theme.