Spam has asserted in his earlier post today that the Portuguese came to the conclusion that Madeleine died and an abduction staged. That was their working premise while Amaral was in charge, but after he left they took a more broad minded approach and their actual conclusion was they hadn't got a scooby do what happened to her and that there was a lack of any evidence against the McCanns (and that's despite the buttons, the sleeves, the dogs, the blood splatter, the frozen cadaver fluids, etc). That's not an appeal to authority btw, it's just a fact.
Also, there are explanations for Smithman within an abduction theory - 1) he was the abductor 2) he was an innocent father like Dr Totman. Descriptions of his appearance by the Smiths were vague and likely to be inaccurate considering the long period of time between sighting and reporting and/or influenced media reports. Anyone who dismisses this as possible or likely isn't thinking straight or being honest with themselves.