Nice theme but theme home page layout incorrect

After long searching I decided to use this (free) theme. It is quite simple to implement. Even a child theme. Three col layout and two col layout templates work fine on all devices I tested.
What not works is the home page template that overrules the WordPress. It becomes clear when a background image is entered. The content region below the header is blue. The region that is claimed by the home-page-widgets is transparent and text is nearly unreadable. This is also in the header region (area 11) the case, even when the home-page feature is not used.
Next to this pictures and slideshows on this homepage are not in the correct size. The full width container for content covers here 100% of the screen width and is not behaving like full-width on the other pages. Left and right background are not visable anymore.

I miss the possibility to add a slide or picture or thumbnail to the widgets that appear on all pages, except for the template homepage. It is not possible to add a slide and text below in a widget.

When the base theme is corrected, this is a fine theme to start with. The add-on plugin could add value, but most could be done with the child theme.