I managed to build the firmware and flash it to my keyboard. The RGB was working and I could even change light effects. That was very promising. Only one or two keys didn't work, and I supposed that only some small adjustment of the pin definition  was needed to fully lit up the keyboard. 

To my surprise, NONE of the keys worked. I mean, if the some pins were wrong, at lest some keys would work. But NONE! I digged more and found that the keyboard is unique due to its optical switches. It means the keyboard need a special set up sequence to activate the optical sensors, and likely the when a key is pressed, the circuit is open, opposing to normal mechanical switches. 

I searched and found some had made QMK working with optical switches, but considering the differences in both the MCU and the switch type, I decided to stop this attempt. The good news is that I was able to follow the help from the SonixQMK project and flashed the stock firmware back to my keyboard, so it's no longer a piece of junk.