No images in the gallery

Hello,
I’ve just updated this plugin to the latest version but now when I create a gallery and select images, when I save, the gallery remains empty. Plugin say: “Your gallery is currently empty. Add items to see a preview.” But if i add items and save the gallery, i still dont see any images. I can’t basically create new galleries and the plugin is useless at this time. What i can do to solve this problem? Uploading a previous version is safe or will break my site?

Thank you!
G