We just released version 1.2.0 of our GGPKG WordPress and Joomla Panorama and Object movie plugins.
The main new feature is that you can see the preview images in the WordPress media library. To make this work we changed the mime type to image/ggpkg so only new uploads will show the thumbnails. It also works for old uploads in the Add Media view.
The new version also fixes some bugs and avoids PHP warnings.
You can download the plugins from our plugin page.