Thanks for your report and for posting the full source of your shortcode; very helpful.
I am running Photonic version 1.56 on my development/test system with the WordPress Twenty Twelve theme. I entered your shortcode on my system and it is working, mostly. I get a strip of thumbnail images below a slideshow of larger single images. The default image size for the slideshow is “full”, so some of the images display over the thumbnails and on down the page.
MLA will pass any parameters it does not recognize on to the Photonic plugin, so you can get better results by adding parameters to resize the slides and thumbnails. For example:
[mla_gallery attachment_category="abc" type="default" style="strip-below" slideshow_height=310 thumb_width=75 thumb_height=75 thumbnail_size=thumbnail slide_size=medium]
You can play with the sizes to get a slideshow that works for you.
I am marking this topic resolved, but please update it if you have problems or further questions regarding the MLA Photonic support. Thanks for your interest in the plugin.
