@leocg The pictures are in my IMVU album. You can possibly access them here: http://www.imvu.com/photos/album/10203414/222014076/
They used to save as .png files, and still show as being saved as .png files, but are no longer viewable in Windows photo viewer and won't open in Photoshop. However, I can still view & use them as normal if I save them from IE (which I prefer not to use). Thanks for your help 🙂