Have you had any luck trying to connect with a higher level supervisor or someone from the creative team for problem solving on details related to your store? It has been so difficult repeating my situation to a new support person each and every call.
There are some work-arounds that work. Several are mentioned on this link. Banner image not showing
Basically, it seems the cache is preventing the new images from showing. So there are various ways to clear the cache. Such as:
Shift+Ctrl+R on your keyboard which reloads the current page, ignoring the cached content.
Hold down Ctrl and click the Reload button.
Hold down Ctrl and press F5. (This one works well for me).
If those don’t work, I’m going to my settings tab in Firefox and going to “Privacy and Security” and then to “Cookies and Site Data”. Then “Manage Data”. Then I’m removing the cookies that say Zazzle and anything that might be related (ie. used in the last 5-15 minutes that don’t seem important or known to me).I
I also find that logging out, restarting my browser sometimes works too.