Quentin - Weird - it doesn't seem to always be the first picture of a set, but it's that way on your last few posts with multiple pictures.
When I right click on a picture to copy the properties url, and then paste in a new tab, the pictures are normally viewable by pasting the address in a new tab.
On one example, this url won't work:
http://i846.photobucket.com/albums/ab22/Quentin_Ballenger/JBJ 28 CF105/Night Shots/IMG_5433.jpg
but this second picture url does:
http://i846.photobucket.com/albums/ab22/Quentin_Ballenger/JBJ 28 CF105/Night Shots/IMG_5434.jpg
I can't figure it out - it's like the picture no longer exists on Photobucket. That's typical of pictures being moved or deleted in Photobucket. The only other explanation would be that the code on those pictures not showing has been corrupted by the upgrade. Even that makes no sense as going back further in your thread the first picture in a set does at times show up just fine.