Box2D4D 1.4.3 Docs
Ok, so I started over again with the latest box2d, and one of the things I did this time, was to give every variable and function a doc comment!
I got it to compile, and immediately compiled these docs.
Enjoy, Box2d fans :-P
On a side note, here's a link to a promising 2D physics engine written from scratch in D, rb2d. You can obtain it with 'dsss net install rb2d.'
Both these projects are one man wonders, so if there are any 2d physics programmers in the D community, feel free to jump in and join the fun!