I thought it had been discussed that the GNR dog trails going around the apartments before crossing the road and disappearing at he car park opposte the Tapas restaraunt may have related to the Mccanns younger children followed by Madeleine following after them going around the apartments a day or so earlier? On their way to the daily creche? Icannot remember whose interview I read that in, but I definitely remember it.
It was in Gerald McCann's statement, made after the dogs went that way;
That, between Monday and Wednesday, not knowing the precise date, when they left the residence by the main door, to place the children in the respective creches, MADELEINE left [went] running to the left to the extreme opposite of the residential blocks where they were lodged, playing with the twins. That they had gone down to the furthest point away from those blocks, not knowing exactly how, the three children got into the gardens at the rear [of the blocks]. Then they followed the inside corridor [pathway] at the rear, next to the hedges [fences] up to the street that led to the secondary reception.
http://www.mccannpjfiles.co.uk/PJ/GERRY-MCCANN-10MAY.htm