There are other posts referring to rebranding. The main issue is that changing the logo URL link. Changing the themes_subs.txt in _base works for some of the themes but for others such as steel changing the URL in steel_subs.txt only changes the login screen not the small logo in the main screen.
Now I have changed it in every themes_subs.txt file , including the 'base' folder, but it does not change anything.
So how do these themes get the default URL if it has been changed in all of the themes_subs.txt file?