We started the PCB design for this project in Fritzing. Since the project started small and simple, it was a satisfactory solution. As the project grew and became more complex, using Fritzing became too cumbersome. A reported bug had tracks disappearing, which made getting the board correct a freakin' mess. We then decided to migrate to KiCad. If the folks over the CERN use and develop it, how bad could it be?! Turns out it was quite easy to learn it (make sure to install the latest version!) and develop the new board, see the image of the schematics and pcb layout: