I think I have solved this problem. See here http://testsite.livejazzlounge.com
I had not realized that the header area only works until one sets some image as header image. The problem had been that I didn’t want any header image, but just the background image as full screen from top to bottom.
So, I uploaded a black line 1920px width x 1px height as header image and the header area now works. I find it really weird that one has to trick the system in this way. The header area shoudl be functional even if one does not haev a header image. You see, if you look carefully, you can see the 1px thick balck line at the top of the site. I can live with that, but if you have a way to get rid of that, even better.
Now the title and buttons are dyanmically adjusted using the % function in header area. Great!
I would like to edit the look (size, no-all-capitals, etc.) of the heading showed before the animated text, as well as the animated text itself. Also, it woudl be nice if one coudl have some control over the size, shape and font sizees of the buttons. In regular pages, these buttons can be readily editied with the SiteOrigin widgets but apparently not on the header area. How does one do all this?
Many thanks! I feel I am now begining to use the full potential of the theme. I am getting closer and closer!