| Hi Psygorn, 
After much looking, rectangle2 node was located here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=7777.1710 
There are 4 "new" nodes in file >>>>>>>>>>>>>>"shapes.zip".<<<<<<<<<<<<<<< 
(Wayne's shape nodes???) 
Unzip the file, and copy the 4   .js files to your %AppData% folder. 
For Windows 10, ...AppData\Roaming\nodeeditor\nodes\extensions.
 
I am so rusty at nodeeditor, it may be that these 4 nodes are not yet integrated into nodeeditor menus.  Not sure. 
They are coded to hook themselves into the Curves2 menu... 
(Circle2, Star2, Polygon2, and Rectangle2)
 
- Brian |