As of dbFront version 1.0.14.3353 you can now easily set the Header and Footer from the Settings dialog found under [Help] / [Settings] / [WebSite].
This same method also applies to the Login Screen where you can also include HTML via the Notice setting. For more details see: Login Settings
With these updates, it is now trivial to select and include a custom logo.
Previous installs of dbFront will need to update the Site Header HTML and Login page Notice HTML to include the keyword {%LogoUri%} which will be replaced with the URL of the logo file.