The old thumbnails updated method would give you the image number where an error ocurred in it's URL. Now, it just stops the bar and I don't know where it stopped last.
Is there a way to see the ID number of the image that caused the error and the update to stop?
Hmmm ... it does normally display what files it has issues with. Make sure the version of CPG is the latest. Without admin access to your site, there isn't a way to determine what the problem could be.
It doesn't show when building all folders
Just the progression bar that stops