The installation instructions in the readme.txt file indicate that the plugin should be copied to a folder called nggallery, but Alex must have removed that requirement since writing that as the code clearly allows the plugin to be installed in any directory below wp-content\plugins.  I initially installed it in the nextgen-gallery directory and it worked fine.

Before the plugin will work, you need to install JW Image Rotator in the NextGEN Gallery plugin directory.  You can get that from  Once you’ve downloaded it, just copy the imagerotator.swf file to the NextGEN Gallery plugin directory.

Now you can activate the plugin.  You’ll notice that there are two NextGEN plugins – a NextGEN Gallery plugin and a NextGEN Gallery Widget plugin.  If you want to display images on your sidebar, activate the widget plugin as well.