The general configuration for Alex! Press is quite simple

theme:
    title:
        fr: 'Alex Press'
        en: 'Alex Press'
    icon: '/assets/user/imgs/icon.svg'
    start: 'guide'

You specify the title in the languages you are using. This is displayed near the logo.
The icon field specifies the logo.
The start field specifies the menu that is going to be displayed when clicking on "get started".