Yes, I managed to flash it. The software was in some error state, and didn't do anything. I didn't know what it will print in the screen that what is doing.
I closed it, and started again. After that I started the flashing again, and it worked, but not perfectly. It stopped after a 1% transfer, and I had to restart the ECU. After that the software connected again and succesfully flashed the rest. I did this two times, and it worked the same way in both times. But it worked!