The blood that was cleaned on the wall and floor. Have you figured out who's it is yet? A murderer would get rid of the weapon and body. Do you think they purposely leave evidence for police to find? I personally think murderers try to cover up their crime by cleaning and getting rid of evidence. Can't think why I could think that - ok I'm lying 
I can find no mention of any forensic evidence from any competent forensic authorities in the SC ruling of an attempt to cover up a living-room massacre.
I'm aware that Amaral is a sensitiive topic, and I tend to avoid him, so apologies to anyone likely to burst a hernia, but I have yet to find even any of his supporters who have been able to lucidly demonstrate his grasp of forensics in the Madeleine case. (No one expects a coordinator to be a forensic scientist, but hopefully should be able to differentiate between relevant and irrelevant.)
I therefore have doubts that he could have been any more proficient in 2004.