gm_alex

This release is a beta release, so error could occur. If you notice an issue please create a issue here: https://github.com/GM-Alex/user-access-manager-nextgen-gallery-extension/issues 
This plugin allows you to use the <a href="https://wordpress.org/extend/plugins/user-access-manager/" rel="ugc">User Access Manager</a>-Plugin to control the access for the <a href="https://wordpress.org/extend/plugins/nextgen-gallery/" rel="ugc">NextGEN Galley</a>-Plugin. You can lock Albums, Galleries and Images.
Feature list
<ul>
<li>Hide albums (if no access)</li>
<li>User-defined album content (if no access)</li>
<li>Hide galleries (if no access)</li>
<li>User-defined gallery title (if no access)</li>
<li>User-defined gallery content (if no access)</li>
<li>Hide images (if no access)</li>
</ul>

User Access Manager – NextGEN Gallery Extension

With this plugin you can use the "User Access Manager" to control the access for the "NextGen Gallery".

Robert Neu

Ozzy Rodriguez

Cipher

The default behavior in WordPress is to generate attachment pages for all of the images in your media library. While this can sometimes be useful, it can also cause problems.
When you upload an image to your media library without inserting it into a post or page, it becomes an unattached image. By default, these images generate attachment pages with no pretty permalink structure. This isn’t very useful for anyone, including search engines.
This plugin takes all of these unattached images and safely redirects them using a 301 redirect to your site’s home page. If you’re using WordPress multisite, it redirects to the current site’s home page. There are no options or settings, just install, activate, and enjoy better SEO and less useless pages on your website!

Redirect Unattached Images

Redirect attachment pages for all unattached images to the current site's home page.

User Access Manager – NextGEN Gallery Extension vs Redirect Unattached Images