Ron Rennick

The functionality in this plugin was incorporated into the built in export feature in WordPress 3.0
Working with a single large export file can be difficult. Use this plugin to create multiple export files that contain sections of your blog. This plugin has been tested on WP & WPMU versions 2.7 – 2.8.4. The plugin may work on earlier versions of WP/WPMU.
All restriction options provided in the plugin are optional. If no restrictions are selected, this plugin generates the same export file as the export feature built into WP & WPMU.
Features
Export by any optional combination of:
<ul>
<li>Date Range – Start & end month/year</li>
<li>Author – Same as WP/WPMU built-in export</li>
<li>Category – Export a specific category</li>
<li>Content type – Choose either posts or pages</li>
<li>Post status – Choose Draft, Published, Scheduled or Private</li>
<li>Blog Tag/Category Terms – Choose whether to include the blog’s complete list of Tags and/or Categories</li>
</ul>
Support can be obtained through:
<a href="https://wordpress.org/tags/advanced-export-for-wp-wpmu?forum_id=10#postform" rel="ugc">WordPress Forums</a>

Advanced Export for WP & WPMU

Adds an Advanced Export to the Tools menu which allows selective exporting of pages, posts, specific categories and/or post statuses by date.

3dperuna

WPMU has great themes and plugins. Unfortunately, many, if not most, come with a nag notice that admins see about installing their notifications dashboard plugin. If you’ve bought one plugin for your site this is probably overkill. If you’re a developer you don’t need this on your client’s sites.
This is a simple plugin that removes the notice. The 1.3 version has been checked against WP 4.4 and recent WPMU plugins, but still should be backwards compatible with older versions of WPMU plugins.
Note: If you do decide to you install the WPMU notifications plugin, please deactivate this one first. Errors may occur if you don’t.
If you like this plugin consider donating: http://www.protospace.com/wpmu-no-nag-plugin/

Remove WPMU Dashboard Install Nag

Works as advertised. Now, why a plugin should be needed for this is another question altogether, and installing and activating this plugin is no substitute for filing an RFE to either add a close button to those annoying nags or a switch to turn them off (and their pref doesn't always work, apparently).
Thanks for this!



Simple and to the point

This plugin removes the nag notice at the top of WPMU plugins and themes.

Advanced Export for WP & WPMU vs Remove WPMU Dashboard Install Nag