I haven't a clue, I see what your talking about. I tried mine and its working correctly, I use the smaller window not sure if that makes a difference or not.
If you turn off the Auctiva scrolling gallery it won't show in your new listings, then you can add the html to your listing on the ones you want, is that your question?
I'd file a support ticket about the error thing though, upper right corner, under help.