Hi, I had the same question today and filed a support ticket...this was the reply:
"Ok, open the listing in your saved listings folder. then in the description editor click the yellow button to the left of the userlinks button.
Thank you
Auctiva Support"
Yet I think images will show in the description area only, I am still a bit confused on this myself. It will not be with the normal pics, I am pretty sure on this, if you have more issues, I too would file a support ticket.
*You should be able to list 16 images in the regular images area.
Calgirl