How to make someone a curator on a Traditional Project

I have recently converted a Collection project to a Traditional project for a variety of reasons, but I am having some trouble with this older platform. First I can’t get a banner photo to fit the size requirements, I have found a forum thread on this topic but it didn’t seem to come to any resolution. Does anyone have any tips to get this to work?

Thanks!

Just make it as small as it says, cut it or resize, even if it’s 3 pixels higher than needed it will be rejected.

feel free to send me the photo in question and I can resize it for you