After several months it lives again.
Thanks Chupito and Harrysmith (from another site) and all that tryed to solve this out.
So, my steps:
1- Open the device and checked that in fact was a RK2738 chip
2- Open RK28upgrade 1.27 with the alterated .inf (driver) and .ini (RK28upgrade 1.27) to VID=0x2207 and PID=0x273A
you can also download the already driver prepared from chupito a few post above. It is for Win7 but if you have XP or other just make the changes like I said.
3- With a small (really small) screwdriver short the 29 and 30 pins of the Hyvix chip like its done here: Rockchip DEAD Player Recovery Guide
4- With the screwdriver touching both 29 and 30 pins, connect the usb cable to the ebook reader. IMPORTANT: you have to keep shorting the pins while inserting the usb plug on the reader. Now wait for the PC to recognize RK28usb. If it says unrecognized probably is because you arent shorting the pins at the same time.
5- After it recognizes RK28usb you can let the screwdriver out of the pins and keeping the usb cable on, open RK28upgrade 1.27.
6- Click on the "image path" button and choose the img file. Chupito provided with his file above, wich worked for me.
7- Now click on "upgrade", wait and it's done