How to group polygons according to distance from certain points and then sort them in 2D

Hi,

I have 64 outlines (closed polygons) of plan views of rooms and the outlines of their windows arranged in a grid (8 X 8). By following the GH definition of David (http://www.grasshopper3d.com/forum/topics/sort-mesh?) I have managed to sort the room outlines in 2D. What I'm trying now is to firstly group the windows according to the distance to the centroids of the rooms' outlines (http://formularch.blogspot.ch/2012/04/gh-distance-grouping.html) and then sort them in 2D as well. In this way, it will be possible to have the same index number for the room outlines and their windows (the same will happen later with doors, fireplaces, stairs, etc)

The problem is in that, the 2d sorting of the grouped windows doesn't seem to be working perfectly. I thought -and tried- different values in the distance parameters of the definition, but it doesn't seem to be solved.

Grasshopper crashes at the moment, so I can't export an image of the definition, but I'm uploading the files. Any help or advice would be welcome.

Thanks in advance.

Periklis