You can install a package from the registry only when the scope is set to All packages:
Open the Package Manager window and select All packages from the package scope drop-down menu.
Select the package you want to install from the list of packages. The package information appears in the details view.
Select the version to install. For more information on available versions, see Finding a specific version.
Click the Install button.
When the progress bar finishes, the new package is ready to use.