The same question has been posted before and here is my findings:
Use the following filter:
// Be aware this removes the inline style for all galleries. (WordPress galleries also)
// You’ll have to add your own gallery styles in your (child) theme’s stylesheet.
add_filter( ‘use_default_gallery_style’, ‘__return_false’ );
Also specify how many columns max you need;
I used columns=”10″
And add the following styling:
.gallery .gallery-item: width:(use your desired width);
WordPress plugins developer should have the ability to assign sticky posts and also the user should have a better way of searching previous posts.