I got the replacement x axis today. No play at all. Looks nice. Greased the bearing from behind.
Now I only have to figure out how I have to replace the axis the best possible way. No instructions added to the replacement part.
I printed around 100h or so with no clog with PETG with PLA Support. Doors closed, top cover removed. I got lucky so far. Ordered the new hardened nozzles anyway. Need to print CF material in the future too.
Edit:
Replaced the x-rail with the new one with the help of this post:
Looks good. No click noises anymore when pushing the extruder back and forth. No play between the axis and the extruder.
Big thanks to the customer support how send a new x rail the other day they received my email.