The songbook is empty because of license issues and the question: which songs should the songbook contain! Everybody would expect different songs. The solution is the internet. There are excellent resources. smartChord finds your songs out there.
Just use ‘Folder’ menu -> ‘New’ -> ‘Internet search’.
You can also google for a tab file collection and import them. Please see also our video for the import: https://www.youtube.com/watch?v=IGM0XnuwtC8