Hi Tomasz, Sorry for the problem. Temporary I set it using Custom CSS in Page setting. We have to make investigation on our side to find a reason.

BTW

Check also Image Layout addon - I think it has even more useful settings that used by you Image Content addon.

And I think I know why nobody noticed that before. All our templates uses Helix and its use bootstrap 3-4-5 and by default it has margin bottom for < p> :

p {
    margin-top: 0;
    margin-bottom: 1rem;
}

and < p > is used in p.sppb-image-content-text. Your custom template has

p { padding:0; margin:0;}

so my suggestion by now is just to use

p.sppb-image-content-text {margin-bottom: 20px;}