Wrong size for thumbnails

Thanks for the question and the shortcode text. Photonic uses a default size of 75px for its thumbnails, and applies the size with JavaScript code in the browser. There is a brief interval between the time the page loads and the size is adjusted, which I believe causes the behavior you reported. You can use the Photonic parameters to set the thumbnail size you want, e.g.:

[mla_gallery attachment_category="gallery" columns="4" limit="20" orderby="date" order="DESC" size="thumbnail" style="launch" thumb_width=150 thumb_height=150]

You can find more information in this related topic:

Photonic Gallery does NOT work with MLA

I am marking this topic resolved, but please update it if you have problems with the above suggestion.