Hi, ya i understand your frustration.
There is no way to edit a relisting except on ebay. When you hit the relist button on evilbay or activa the ebay "review your listing" page will open. On the bottom to the right of the "List your item " button there is the link to "Edit listing" in blue letters. That is how it is done. Now if you wish to change photos to a relist or active listing you may do this with auctiva under the "add images" under the listings/active tab. Or you can replace photos under the images/manage tab. I replace images that i do not like this way. The first way adds the photo to the bottom of the auction page.
Hope this helped.