Thanks for your question. The [mla_gallery] shortcode, like the WordPress [gallery] shortcode, defaults to showing only image items from the Media Library. To display other items, such as PDF documents you must add the post_mime_type parameter to your shortcode:
[mla_gallery attachment_category=ge post_mime_type=application/pdf]
There are a couple of other parameters you might consider. The link=file parameter will create a link from the gallery items directly to the PDF documents. The size=icon parameter will replace the document title with a PDF icon. You can add mla_caption="{+title}" to put the document title under each icon.
You might also be interested in the “Thumbnail Substitution Support, mla_viewer” section of the Settings/Media Library Assistant Documentation tab, which describes how to generate more interesting thumbnails based on the document content, or supply a “Featured Image” in place of the icon.
I hope that gets you started on composing your PDF gallery. I am marking this topic resolved, but please update it if you have any problems or further questions regarding the above suggestions. Thanks for your interest in the plugin.
David, thank you for the outstanding response. Not only did you address my question, you supplied many more options I have not yet run into yet. Thank you so much for the very clear and precise answer.
