also added a very handy SVG pipeline. you can make fem documents in inkscape and whatnot now.
added a few examples. use content-info to give your object a material (the title under accesability that way it serves a secondary purpose)
class names:
Segment
Node
Block
you can claim a rectangle to be a segment, it will create an enclosed object out of segments for you.
you should trim your objects to overlap just a smidge or you get some ghost nodes.