This is the CI20, if you are looking at this, you probably have one. Flashing a new image to the CI20 is far from a difficult feat
Step 1: Getting Images
First, get yourself a NAND image from http://elinux.org/CI20_Distros Like the beta Debian 8. or any of the other Linuxes that are presented there. These will be in .img format.
Step 2: Mounting to SD Card
Hopefully, you have an SD card and a way to connect it to your PC. Plug in your SD card, and get Windows32 Disk Imager (https://sourceforge.net/projects/win32diskimager/). Select your F: drive, and the .img file for Debian 8, Debian 7 or the other NAND images.
Step 3: Write!
Write it to the SD! (Click "Write").
Step 4: Ok!
When it's done. Eject the SD card, we will now work with the CI20. See where it says "Boot Select" In the image above? At that place, there are 3 little prongs. The ones labeled 1 & 2 will be shorted by default. Just move the little connector over so that 2 & 3 are connected. Insert the SD card into its slot and turn on the CI20. The little LED will turn red, and then blue. After ~10 minutes the light will have gone back to red. Unplug the power, and replace the connector so it shorts 1 & 2 again. It will now boot with whatever version of Linux you installed.
Please note that your SD card will now be a smaller size than it was (Less storage). Delete all the small partitions and make one big new one formatted to FAT32.
Thx for reading.