I thought you were using the plastic guide tubes internally. Just curious, you don't find using the full cable housing on the RD a bit stiff? Usually the supplied cable on Shimano rear derailleurs tend to be more flexy.
Yes, it is stiff, but since the frame is fully integrated I don't see any other way of routing than 1 cable from front to back with outer housing. There are no stops anywhere in the frame to stop the cable...
After a couple of indoor rides I have a better feeling of the frame. I had to replace the carbon seat by my standard seat to decrease the setback of the saddle (the carbon does not go forward far enough) and now my seat is in the most forward position possible... I could have seen this coming because the TFSA frame had the same and this had a less slack seattube angle... I am aware this problem will not impact a lot of people because I seem to like a more forward position than most (kneecap right above the pedal axle is too far back for me, so I set it a few cm more foreward)...
I have asked Hygge if they have a 0mm setback seatpost, but since there is non on their webshop I expect the answer to be no...
Edit: I also asked the Ali store that sells the Winow frame (same frame). There is no seatpost without setback for now, but if I order 100 they will design one
Edit #2: Hygge also said they don't have it and suggested I search Aliexpress to find one that fits. But the ones I find are not the right size...