I've built this GBC module and it recently debuted at our Brickish Weekend event at the National Space Centre in Leicester, UK. I've had to change the dark green parts to black due to parts availability as well as use the current moulds for the transparent panels.
This is Huw's video of Sunday's layout, the module is halfway round:
The mechanism worked ok for the most part, main issue I had was that when the tipper emptied the balls they sometimes would come out at a slight angle and get jammed against the two moveable doors which are used for circuit mode. This prevented the tipper from returning to the upright position. I need to widen the exit chute to make it more forgiving. There was also the issue of balls collecting around the bottom of the wheel so I need to put in some cheese slopes or similar in to nudge them a bit but without the risk of the wheel getting jammed.
For a first event it ran very reliably.