UPFRONT: How do I link the page header logo to main page (as in a normal Wordpress site)

Hello!
How do I link the logo image that appears in the header of each page back to the main page? It should be simple but I'm having no luck…
Thanks!
PS: I'm using Upfront and to be honest, for a design engine that's supposed to make it easy to create sites, it is just the opposite. I'm used to having more control!!!