Whilst searching the archives for some of my previous posts, it's very disappointing to discover that many of the photos (yet not all?!) that I have posted over the years have either disappeared or the links have broken. Unlike many other contributors who posted vis Imageshack, I have maintained a fully paid-up imageshack account so there is no reason for them not to be there.
The archives are a mess.
Have you checked that the photos are actually still on ImageShack? IIRC they auto-delete images which have not been viewed within a certain time frame - although whether that applies to paid accounts I don't know. A few of mine - on a free account - have gone AWOL for no obvious reason: the URLs are still valid, but the images are blank.
A quick google for 'images disappearing imageshack' brings up many complaints about lost pictures, so I'm not sure that this is necessarily a matter which can be blamed on the new format.