Krzysiek
That "someone" was me.
I use either X8 or flat 8 firmware depending on how the motor rotations are defined. I operate mine with all of the top props spinning clockwise (pusher props) and the bottoms spinning counter-clockwise (tractor props). Using a flat X-Okto you just assign the right motor numbers to the top and bottom motors. I usually have motors numbered...
Front left (Top is #1, Bottom is #8)
Front right (Top is #3, Bottom is #2)
Back right (Top is #5, Bottom is #4)
Back left (Top is #7, Bottom is #6)
Does that help?
Bart