Hi Lyn, welcome to the forum.
Did you open a copy of the template file? In the package you downloaded, there is a Sibelius file called "S7S_Template_7.1a.sib". Make a copy of this file, rename it, and then open it, you'll find the S7S Template Ensemble of instruments. You can also follow the directions on how to Export Manuscript Paper on page 24 of the Readme.
Let me know if how you get on.
Hugh