Let me start off with this is way easier in Poser 13. It's basically 1 click to add all the included content. That said let's add the included libraries to Poser 11.

Poser 11's included content is a series of Zip files available for download from the PoserSoftware.com site. https://www.posersoftware.com/downloads/content/11 (That link will ask for you serial number so have it handy.)

Download all that you want to include. Save the zips. Don't let your web browser "help" by extracting the zips for you. They need to be zip files for the next step to work.

Open Poser and from the top menu choose File > Install From Zip Archive ...

Choose one of the zip files you downloaded from the system file chooser.

Now select a library to add the content to ...

Click install and the content from the zip will be added to your library,

After installing content it's recommended to restart Poser to be sure the newly added items show in the library

Now the new content will be in your library

Happy Rendering