Okay, sharing the project will be on my list,
btw, I just visited the company here in TW had some talk with the manager, and complaint about everybody thinks, the poor datasheet dimension quality.
It turns out that the datasheets are more clear when sizing now,
not sure if its because my complaint anyway.
5050: apa102c-5050 (c is a cheaper package, and possibly made in China)
2020: apa102-2020 (8-pads as this thread using)
I heard that they are also releasing apa102 in 3535 / 1515 package, but the new datasheet are not released yet, they follow nearly the same 6-pads with apa102-5050, with different arrangement of pins, so its easier to chain.
and there is also a new 2020 package, with 6-pads only, for more easy/dense soldering! not-yet seen datasheet release,
please wait for my discovery