where to find GK Menu Extended Parameters

Hello, I started using your templates and I begin by installing a template (GK_MUSIC) on an existing site. My first intention was to stall the main menu. And I find that I do not have the module "Menu GK Extended Parameters" that exists on demos of the template. Where can I find this plug-in ?

Thank you and best regards.

Honestly a small text explaining more clearly where the file is named "rest ..." would be respectful of those who started ...
So for beginners those files "the rest-files package" are add-ons to the template.

No thanks, but with respect.