Thanks for reaching out.
The knowledge base for Pro header/footer are available here https://theme.co/apex/forum/t/pro-header-and-footer-builder-introduction/103. It maybe outdated for sometime due to the updates and changes but we'll surely update it based on the stable and current features. And yes, it's a bit complex at first and features are not simple, it's meant for advanced customization and there are a lot of options to make it more possible.
May I know what part of documentation you're checking? I can forward it so we could check if we can update it right away in case something is missed. I can't personally monitor them but I'll be more happy to forward it to the right person .
As for your main question, do you wish to stack your logo along with the headline then center it? I guess that's what you're trying to do . Then please follow this
1) Make sure your logo and headline are on the same container
2) Inspect your container (where your logo and headlines are) and set its
Flex Layout to
3) And set the container's horizontal alignment to center
4) Optional, please set the
Flex preset to
Fill Space to make the container full-width. This is recommended for a single row footer.
Hope this helps, and let me know if you have further question regarding these settings.