Wow, awesome job! I have bought RENAISSER 520C, which is supposedly a really good pen, but it was so bad on the Minibook X i stopped doing any handwritten notes. It is so much worse than Wacom EMR I was using before, completely unusable for handwriting in my opinion. Oh and on Linux it actually is even slightly worse than on Windows, like if polling was even lower or smoothing even higher.
So if it works reliably for you for a few days I would really want to mod mine too, so the pen becomes actually usable.