As for the original question - to access the filesystem of the binary you must
1) Use the flasher tool to extract the root file system (in OS2007 that file was called rootfs.jffs2)
2) Then loopback-mount it as a jffs2 filesystem.

Unfortunately 2) isn't as straight-forward as loopback-mounting other filesystem types, but I did it after a little googling. You'll need some extra kernel modules (on your desktop linux box) because jffs2 is a special flash file system.

After that you should be able to access the filesystem on your desktop and get files from it - whether that would be at all useful is another question (I don't think it's easy to mix and match OS2007 and OS2008 applications, at least not GUI apps).