Hello @kateanita,
Thanks for writing in! The Essential Grid plugin is bundled in the theme. You can create a grid and have all the features and functionality of the plugin. We will be providing the plugin updates. On the other hand, the creators of the plugin have changed their policy that the Essential Grid template library will be exclusively available to users who buy a separate plugin license. This is the reason why you are prompted to activate the plugin when you try to access it.
Hope this explains your Ess. Grid template library issue briefly.