2013... ohoh!
Fired by this in 2016 (OMG!):
http://forum.bioware...bject-into-nwn/
I tested this "placeable+WOK"-thing creating a placeable with a size of a 2x2 tile. I placed the AuroraBase in the bottom left center ("tile center") and in this case, the WOK override only worked in the bottom left "tile area". In any other parts of the placeable the WOK override didn't work.
2nd I centered the AuroraBase to the placable, but that didn't work either.
So, it seems, this is "limited" to a placeable with the max. of a tile size.