images for the Creative Commons license aren't displayed

Greetings.

1. I've set the Gallery media format to "Media files" (or equivalent, I'm using a localized version) instead of the "Gallery media" format here:
/admin/structure/types/manage/media_gallery/display/full

This way, the styles I've specified here:
admin/config/media/file-types/manage/image/file-display/media_gallery_thumbnail

work (as in, I can see the tags and the images aren't *increased* in scale regardless of my settings).

However, in this case, the CC license images aren't displayed, but I'm shown the license shortcode, such as
cc_sa_nc

The corresponding settings are set for the gallery_thumbnail style.

2. If I set the "Gallery media" field format to "Gallery media", then I can't see the Creative Commons license at all, despite it being set both in the Structure/Gallery settings and the Configuration/Multimedia/Styles settings.

Of course, I can see the CC images on the gallery_lightbox display (along with the tags), but the gallery_thumbnail style doesn't show me anything except for the image titles.

What can I do to see the CC images and tags in gallery_thumbnails with "Gallery media" correctly? Right now, the image styling is satisfactory despite using the "Media file" format, but, apparently, it's deprecated.

Thanks.

P.S. Apparently, images scale in size thanks to CSS, or something: #1533024: where can i set the size form this picture-'frames' in the teaser view?