Sometimes, due either plugins or themes conflict you might get an error message in your WordPress site when activating the plugin. It doesn’t meant that the plugin has a bug but the plugin is conflicting with another plugin. It happens from time to time and can be resolved quickly.
If for some reason you’re not able to get in your WordPress Administrator right after you’ve activated the plugin you will need to get in your plugins folder via ftp and rename users-control folder, don’t remove it just rename it. Then try to get in your WP admin, since the plugin’s folder changed WordPress will deactivate the plugin automatically.
Please contact us if that happens.