I could install Dingux just fine. I have tried various reflashing programs to try to unbrick my Dingoo but have never had any work, yet I have always been able to reflash Dingux back on it and it works fine.
Any reflashing program I use always gives me the UNAUTHORIZED screen. I still use my Dingoo every single day however, with Dingux. I really miss some of the things I could do in the native firmware, but at least it's not a total loss. I use the SNES emulator in Dingux often and it works really well.
Also the difference is when you reflash using a program on your PC. I used the method of updating the firmware where you copy the file to the root of the internal memory and then hold the down arrow when you restart and that always worked. I changed the firmware a few times and they always worked, even did a custom one jsut fine, but always had the issue with homebrew games. One day I was pointed to a thread that suggested an unbricking tool... and that's when I bricked it.