Yes, it seems the more each site upgrades, the more time it takes to list and figure out what they've done now.
When you are trying to edit a listing in eBay, some things such as text are quite simple but if you're adding or deleting pictures I find the easiest way is to do it through Auctiva.
You make all the changes through your saved listing and Save. Then you have to go back and click on the icon for HTML. You click on 'select all' and right click to copy. Then have to go back to eBay, go to your listing and go to item description & click on the HTML tab. Delete all that is there and then paste the html you just copied in Auctiva. This new html includes all your revisions and changes. I know it sounds more difficult than it is.
If you need specifics I can do some screen shots so just let me know.
Again, as to whats up with those thumbnails, I don't get that at all. I hope when you recieve a response from support, you'll come back & let me know what the glitch was.
It used to be so much fun...now it seems like it's hard to sit down and focus knowing the obstacles. Don't give up!