i see that you have set on the page /our-clinic/about for the other cell a min-height – that will be possible if you want only the flip-background image to cover only ( including crop ) – you have to remove all paddings on that cell with the flip-box and set the same min-height / height option there !!!
my method above is only to have totaly responsive bg-image for flip

you can test if for the above page by:

.av-layout-grid-container.av-li73q-e1db10c26939acc99331ee70921182c6 .avia-icongrid-flipbox .av-icon-cell-item .avia-icongrid-flipback,
.av-layout-grid-container.av-li73q-e1db10c26939acc99331ee70921182c6 .avia-icongrid-flipbox .av-icon-cell-item .avia-icongrid-front {
  margin: 0 !important;
}

.av-layout-grid-container.av-li73q-e1db10c26939acc99331ee70921182c6 {
  min-height: 500px !important;
}

.av-layout-grid-container.av-li73q-e1db10c26939acc99331ee70921182c6 .avia-icon-grid-container,
.av-layout-grid-container.av-li73q-e1db10c26939acc99331ee70921182c6 .article-icon-entry {
  min-height: 500px !important;
}

.responsive #top #wrap_all .flex_cell.av-5cyqiu-1b136132ec762676c6173331de16be40{
  padding: 0 !important;
}

i would give the grid-row a custom class or ID and set the css for that.

does your page have on html a lang attribute?
because your pages are password protected i can not inspect it.

for polylang try in child-theme functions.php:

function av_change_logo_link($link){
	$lang = pll_current_language('locale');
	switch ($lang) {
		case 'fr_FR':
		$link = "https://backlink_to_french_page";
		break;
		case 'de_DE':
		$link = "https://backlink_to_german_page";
		break;
	}
	return $link;
}
add_filter('avf_logo_link','av_change_logo_link');

adjust your languages with the examples given above
____________
or shorter if it is one default and one extra lang:

function av_change_logo_url($link){
    $lang = pll_current_language('locale');
    if ($lang == 'ro-RO') {
        $link = "https://your_needed_link";
    }
    return $link; 
}
add_filter('avf_logo_link','av_change_logo_url');

guess for Romanian it is ro_RO

i guess i took the plugin above because some of those tools do not remove the already existing thumbnails.
one plugin that is more clear in this is: https://en-gb.wordpress.org/plugins/regenerate-thumbnails-advanced/

it has a clean-up function “Delete unused Thumbnails”

if your language plugin set the correct lang attributes to html – you an use it as:
( this example is for german pages a new logo link)

function av_change_logo_link_on_different_languages($link){
    $currentlang = get_bloginfo('language');
    if($currentlang=="de_DE"){
        $link = 'https://lang_specific_link';
    }
    return $link; 
}
add_filter('avf_logo_link','av_change_logo_link_on_different_languages');

see: https://kriesi.at/support/topic/still-fighting-with-managing-default-image-sizes/#post-1418393

or: https://kriesi.at/support/topic/bilder-speicher/#post-1422743

Read the comments carefully in those snippets – some image-sizes are needed for backend to work.

i try now your setting of background-image on front- and normal flip under that demo

btw. this only works – if the content of the other cell does not need more space than the height-setting
then you have to break at 989px – and if that does not work too – you have to live with those spaces ;)
Because the cell with more content (space for that content ) determines the height of the grid-row.

Das Menu, welches dir oben bei Enfold angezeigt werden soll muss in den Menü Optionen angewählt werden: Punkt 4 im Bild.

(click to enlarge the image)

Wenn du also dann via (1) ein neues Menü erstellt hast (Benennung bleibt dir überlassen) kannst du Menüpunkte (2) dem Menü hinzufügen. Solltest Du also “Startseite” ( im Bild home da ich die Seite auf englisch führe) hinzugefügt haben, dann kannst du bei (3) den Pfeil klicken. es erscheinen die Optionen zu dem Menüpunkt als Dropdown. Hier kannst du bei “Naviagtion Label” etwas anderes eintragen.

PS : solltest du nicht so viel angezeigt bekommen wie auf meinem Bild dann sind oben rechts in dem Dropdown nicht alle Optionen ausgewählt.

By the way – afaik – WordPress limits upload size not only to a file size but also to file dimension of 2560px every image that is bigger is saved as filename-scaled or something like that. If you do not want this behavior and upload bigger images in file-dimension use this snippet:

add_filter( 'big_image_size_threshold', '__return_false' );

or if you like to set it to a new treshold :

function redifining_big_image_size_threshold( $threshold ) {
    return 5000; 
}
add_filter('big_image_size_threshold', 'redifining_big_image_size_threshold', 999, 1);

Yes that is true but for my part, however, I try to activate the Advanced Layerslider for performance reasons only in Enfold installations where it is absolutely necessary. That means really complex animations have to be realized. That’s why I usually deactivate it in the settings (always in such a way that it can be reactivated if necessary).

I’m afraid this is a relevant upgrade requirement for your website. As a shop system provider, you are in contact with your customers and collect personal data. As far as I know, this new feature is then mandatory.
To what extent it makes sense for a small percentage of all Enfold users to incorporate this functionality into the GDPR concept, which is already quite well included, remains to be seen. I fear that this would make the theme unnecessarily unperfomant for those who do not need it.
Rather, I believe that a store operator is better advised to use a highly specialized plugin to ensure legal compliance.

sorry – wrong suggestion – you said that you have set the checkbox on your user account.

Nothing! On that Demo – the landing page is a page with transparent header.
You can set this logo for transparency header – by checking that “Transparency Logo Options” under the logo input field on enfold option.
There a different logo could be set for it.

on that single post : https://avaansmedia.com/when-should-a-startup-hire-a-pr-firm/
edit the content of that single post under that audio embed: “When Should a Startup Hire a PR Firm?” to h2

and – you had to adjust the padding-top of #main in your setting.
i can see this rule inside your css:

body.category #wrap_all #main, body.tag #wrap_all #main {
  padding-top: 0 !important;
}

that is why there is an overlap with your logo.