Homepage setup with header image

Hello,
I would like to set up the GeoDirectory Modern theme homepage with a header image (to replace the map).

1) In a previous support request, you suggested a width of 1900 px. I added an image at this width but I would like to know how to reduce the image height – I have a width of 1900 px but the image height is 1900 x 1242 and then GeoDirectory compresses it.

2) I’ve inserted the image on the homepage but there is a white gap above the image and below the upper menu buttons. How do I get rid of the gap?

3) The ribbon of categories/CPT types that was over the map has disappeared when I disabled the map, is there a way to get them back so they are placed over the image – at the bottom of the image?

Thank you.