Ok, one problem I see is that several files that you've edited are saved in UTF8/Unicode with BOM.
What you need is find these files and save them either in ASCII or if UTF8 is a-must, then find an
editor that allows you save it without BOM. Windows' notepad and wordpad are not suitable for this.
It's an extra 6 bytes at the beginning of the downloaded images, so I assume there are at least 2 files you've edited.
global.php - definitely has BOM in.