After hours, days and weeks of testing, modifying and testing again, the results are in this video:

I am still behind the timeline marked by this years HackadayPrize (which really pushes me...), but the results I got so far should really help to improve the design of my CNC v3.x series.The plastics thread linkage is the best drive I have built to date. Looks like science isn't a bad approach to get better machines ;-)