They were foolish to persue this case against Gonçalo Amaral while Madeleine remains a 'disappeared'. If she had been found alive they would have had a case but as it stands I don't believe they can prove a libel. Instead, all they have managed to do is to promote Amaral plc to an even greater extent.
As far as hindering the worldwide search is concerned I believe his book improved the chances of her being found.
Tend to agree with that and also how can they prove he libelled them when Madeleine just remains disappeared! and the case unsolved. And not forgetting the interim police report and the final legal summary....which concluded they have no idea of what crime was committed or by who albeit the PP did say something along the lines of it being difficult to see how the mccanns were involved, but still, no clearance or resolution
Eta
I must also say that had she been found alive post the book...it wouldnt have changed anything as that is what Mr Amaral thought at the time......and also something the investigation did not refute at any time.....
people should read what the higher court said too, and reread
http://miscarriageofjustice.co/index.php?topic=2168.0