Unfortunatley same here too.
I created and published a gallery, but then I cannot insert it in a post.
In the post, I insert gallery block, in thise block, I can reach the gallery selector, I pick and select my gallery, the button at botton right (Insert the gallery in the publication) becomes active…. but even I click it, nothing happens ! Nothing changes on the page current page. Only escape is … to cancel :(
WP 5.5
Responsive Lightbox & Gallery
Hoping we can enjoy it soon, this is my first try and it looks really great !
Thank you.