I was testing out the site from another computer and came across a bug. When viewing a product and you click “View Larger Image”, it pops up the larger picture and has thumbnails for the other ones. Mixed in with the thumbnails is another small image… I noticed the thumbnail when in design mode and thought that was the culprit… However since I’m on a completely separate computer and browsing anonymously, it still shows up. I attached a picture of what I am referring to.
I deleted my cache/compiled folders in hopes it would solve the problem but it didn’t. The browser is IE 7 and also FireFox 3.5.2
bump for some help
The problem lies in JS/Previewer.js … I reverted back to 2.0.8’s file and it solved the problem… so I compared the two files and found the line that changed.
v2.0.8
previewer_thumbs += '';
v.2.0.12
previewer_thumbs += '';
I was running into this same issue and replaced the one line and it solved the problem. 
Thank you RacingSolution.