These chairs are terribly difficult to assemble for a few reasons. One is that instructions are really google-translate to English with corresponding quality. Second is that one of the reinforcement bars in a middle of the chair is near-impossible to install (one on the back near the legs is also very difficult) - reason is that it is used to stretch-out chair material to make it flat - but as a result installing a screw into the place near-impossible. I had to use 3-ton jack to get it done - see picture.
Also paint is easily stretchable, all screws and nuts are in exact quantity and if you loose or cross-thread one you are out of luck. 
I really regret I've purchased these.