Tilted Rotors: My first GBC module

For years I've been saying that I want to try to build GBC modules, too. Ever since the first LEGO Technic sets were launched in the late seventies, I always had a weakness for LEGO Technic. But what would be the best possible way to start building?
On LEGO.com you can find an interview with Akiyuki Kawaguchi, one of the best LEGO Technic builders out there. In the interview he states that beginners should start with copying existing modules of other (more experienced) GBC builders. Unfortunately, building instructions for GBC modules are hard to find...
I decided to follow his advice and try copying an existing module. I watched many video's on YouTube to decide that copying a module of the master himself would be challenging enough... Images of his creations are rather scarce, and always very well hiding certain details. Watching his YouTube video over and over again was required to figure out the details.
I had only one restriction: I decided not to buy new parts: I would try to build the module with parts I had in my own supply. That complicated things a lot, and I had to 'borrow' many parts from my children's supply, too...

And when I had finally finished the module, I came to the conclusion that almost a third of the balls didn't make their way through the module like they were supposed to. Had I done something wrong? And only than I noticed his remark attached to the video: "ball spilling is not zero"... Damn! So I had to find a better solution. With a few hours of try and error I managed to solve the problem: only 2 balls out of 300 fell out of the module. Not too bad, I guess.

I have the impression that Akiyuki Kawaguchi hides parts of his creations on purpose,
so I decided to respect his choice and not to give you too many details as well.

After approximately two hours of continuous rotation, I had the impression that it was slightly slowing down. And all the sudden it stopped!... What happened?
I replaced the M-motor with a L-motor, but with no visible improvement. I even tried with two parallel L-motors, but then I heard gears breaking...
The cause? I only had 3 turntubles (new type) at my disposal, so I used one old type turntable. Because the old turntable is a lot bigger than the new one, I had to use more gears to work my way around it. The combination of all those gears with the friction that the four turntables generate (because of the odd angles) was enough to make the module very unreliable.

So I had to head over to the design table again and make some changes: I took apart another creation to retrieve one more turntable. Now I could try again to make my module look a bit more like the original. And with some try and error I managed to reduce ball spilling, too!

Still not giving too many details...

I took my creation apart... very, very slowly to make an MLCad-file of it. You never know that one day I'll want to build it again...