I can't edit the theme in my form, I need to get rid of the photo at the top.

I picked a theme, added a photo which is too big. I added the photo header the way I wanted from the form builder now I can't get rid of the big photo that was part of the theme. I see no where to edit the theme or background. 

May I know which of the element in your form you want to remove? Are you referring to the image with the dog?

I checked that form and it is not really part of the theme, you can delete it by selecting it in your form builder and click the "x" button. Here's a screenshot:

That should delete the image field there. Let us know if you are referring to a different element.