Guest access to courses and organsations should be possible in Ultra Course View, as it is in Learn Classic View.
We regularly use Guest access to Organisations in our Managed Hosting system and would hope that this is still available in SaaS with Ultra Base Navigation enabled.
It seems that by default you are presented with a login page on SaaS Ultra Base Navigation (like Coursesites) and I'm not sure if you can make the Institution page visible to users before they have logged in as you can do in the Managed Hosting system with Community (tabs/modules).
I experimented with an Original View course in Coursesites enabling Guest access and then trying the link to a guest-enabled content area but this just presented the user with the login page rather than taking you directly to the content area which is what currently happens on the Managed Hosting system.
It appears that when you enable Ultra Navigation in Saas, guest access is deprecated. More about it here: Guest Access - link generation tool for Ultra Navigation
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