Pieter,
usually it depends on where you are viewing the forum from and where the images are linked from. I've noticed at work that if photos are linked from places like photobucket I can see them but some other more obscure hosting sites my works system will block access to those sites and all I get is the dreaded little red X.....it maybe your security settings by your employer doing this..............if indeed you are currently at work that is.....
Nice work mf, clearance won't be an issue now will it.......hehe.
Cheers,
Matty