Both the C2531 and the programming module are recieved and working. Additional flex cable was also provided by the seller in the package.
This is not five stars order because the adapter is not the one presented in product description. The adapter that I got, as can be noticed in my picture, has both connectors soldered on the other side of the PCB so therefore all the wires positions are mirrored. As I was flashing such a dongle for the first time in my life I had issues in getting the correct connections.