Hi SWT. I already saw all your video.
More K9/X3 video please!!! 
How to install super user, how to start recovery mode would be great too!!!
Thx
X3/K9 is almost the same as X1/D5 plus the 2nd button.
So, you can refer to X1/D5 for almost everything.
I still didn’t find the stock firmware for X3/K9 or X1/D5, can you please give me the link? Thx
Latest post in the ROM and Firmware Releases 
I was certain that I answered this question before…
Anyway the above answer is correct and it was posted by Lokifish Marz