Do you apply the image as the background? If you do not, try background, if it does not help, contact us with credentials. We will look into it In any way, the theme does not influence.
By default, our header has a margin bottom and if you want to remove it on your home page, you can simply add a negative margin top for the first row on the page with WPBakery page builder. So just set -40px for example to compensate it.
Please, provide us an admin access to your new domain where we can switch between them and compare how it works. Currently, we don’t see any issues with our theme. And we showed this on screenshots to you.
But it is not our theme issue but the problem with the slider. Seems that it is cropped when stretch row option in WPBakery is enabled. It is not our theme option but comes with WPBakery page builder.