Creality CR-10 slightly jerks when moves from right to left So when CR-10 prints square (like on the video starting from 6 second) while being in the top right corner extruder jerks i.e. slightly moves to the right and then continues movement to the left. So the resulting prints are not so nice:

What can I do? I don't see issues in assembling but I almost definitely have them. What can be wrong?

UPDATE: Printer settings: nozzle temperature - 180, bed temperature - 65. I calibrated extuder according to the video. Bed level seems to be ok for me. I started using Difamix because of bed adhesion (sometimes even using IKEA mirror).

Here is my calibration cube size (I wrote only edges different from 20mm):



And here is the issues with calibration cube I found. Top layer:
 
Bottom layer:

Layer with Y is a bit rough (not a big issue as for me):

Also edge between X layer and Y layer is not very sharp, a bit rounded.
It looks like the nozzle is not perfectly perpendicular to the bed. It is also dragging which might indicate overextrusion or bad z stop calibration..