Ok, so I've worked hard those last days trying to fix the issue mentioned earlier. At this point, it seems clear to me that the magnet should be as close as possible to the sensor, and as small as possible.
I took it as an opportunity to work again on the sequential behavior that deserves a better treatment, and those tests helped me to understand what we need to do to make it great.
It meant to upgrade the design of the carriage, the slider, and the sequential track. So please try them together.
Recent tests with a 4x2mm magnets with the pcb close to the slider gave good results. I have attached the files required if you want to test this solution. The body2 is still the same, but there is a big spacer now, and you will need a longer m3 bolt, something like m3x16.
So now, this is the end of the V1.0. I am working on the v2.0 of the pcb with a layout adjustment : the screw and the header will be moved a bit a part so we can have the magnet as close as possible to the sensor. Body2 will also be updated to get rid of that ugly spacer.
It will take about one month (so better count on two) to get the pcb ready to ship. Everyone who ordered the V1.0 will received the V2.0 pcb for free once it's ready.
In the meantime, I will work on making that sequential mod feel great !
I also plan on designing a main pcb with an added 5V pin for the HSS and a dedicated header for the eclutch.