The project is on Dangerous Prototypes blog
isoUSBRS422 is an open source isolated USB↔RS-422/RS-485 converter board. All files and detailed explanation are given on the Github repository. In addition to project files, some project steps are given in the following log posts.
Posts related to the project
isoUSBRS422 is on EEVblog Mailbag section
I published first version, v1, of isoUSBRS422 project.
Short review of isoUSBRS422 PCBs from dirtypcbs.com
I got my boards
Boards are on the way
I am starting an isolated USB RS422 converter board project