Custom-header-images

Hello,

I’m having trouble uploading images in the header of my WordPress site? I send you below the link that visually explains my problem. Furthermore, I have to take an old theme WordPress 3.0 (did by someone else who not available anymore) and try to make it work on the new WordPress 4.4.2. I’ll admit that is difficult, I try many things and I’m lost! It’s tough because it’s a reskin of the twenty ten theme. Everything else seems to work except the header-images and it’s the most important thing in my website. The idea is to put the header-image behind the black square logo Centre Design and can be different on different pages of my website, but the message appear constantly when I try to change some proprieties of the header in the dashboard of WordPress?

That’s my site:
http://www.centrededesign.com/wordpress

That’s the problem:
http://www.centrededesign.com/wp-admin/admin.php?page=dhnd_add_menu

In fact, I was wondering if somebody can help me to make this kind of header-images change on my WordPress site?

Thank you very much!

Best regards,

Genevieve Le Guerrier