The plugin is working but there’s still a conflict with lightbox script used in your theme (2 script are applied for image enlargement)
When it comes to the gallery – each of those links opens a different page where images are displayed in a slideshow gallery. Again, this is the feature of your theme (quite nice one by the way) but there is no easy way to change it’s bahavior (those are not image links, but page links).
All the problems you are facing have one thing in common: you are using a theme that has quite many built-in functionalies. When you try to change those functionalities by means of the plugins, it’s not being replaced but duplicated.
I think you should try to consult the theme author, on how to modify the theme he/she created.
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