I know this thread is old but for anyone that is still searching, just wanted to let people know that it possible to run LibreELEC with Kodi 18.1 on G02REF STVMX using the build found in the following thread.
[9.X-devel] LibreELEC builds for g02ref/g18ref_th2 (Prima PM-6001, VS-IP166, VS-IP015, ...)
As of the time of this writing, the link to the release build is stated incorrectly. It should be the following instead:
libreelec-amlogic_g02ref.arm-9.0-devel-20190307225115-0e98e15.img.gz
I have it working on my VMedia VBox that is similar to the Geniatech / MyGica ATV 1200 but without the TV tuner HW. I have run MyGica builds for the ATV 1200 on my box so I assume it should work the other way around too.
Follow the instructions in the above thread to write the image of the LibreELEC build onto a SD card. There are 2 things you need to do to get this to load and run on GO2REF STVMX.
1) Rename the aml_autoscript file on the SD card to factory_update_param.ubt because the STVMX box expects a different filename.
2) You have to use the toothpick method to boot the kernel from the SD card. That means unplug the power to the box, insert SD card, use a pointed instrument to press and hold the reset button while you plug back the power, keep pressing for about 10 seconds and then release button. If successful, you should see the LibreELEC logo screen appear soon.
The first thing that will happen on initial boot up is it will resize the initial 32MB ext3 partition on the SD card to make use of all the remaining unallocated space on the SD card. Depending on the size of your SD card, this could take a while so please be patient and let it run to completion (I recommend using a 1-8 GB card to do your initial testing). When done, you should see Kodi 18.1 logo screen appear.
One thing to note is that wifi doesn't seem to work on this build (not for me at least). I have to use an Ethernet connection instead. Also, there are some additional steps needed to get the remote control working which I haven't done yet. Instructions can be found on other LibreELEC forum threads. Use a USB keyboard with touch pad if you got one.
Since it was a little cumbersome to have to use toothpick method every time to boot LibreELEC, I modified the environment setting of the bootloader on my box to prioritize booting up from MMC over NAND flash if the above script exists. Now LibreELEC boots up from SD card by default. Since this step is quite involved and can result in a bricked box if not done correctly (for which I assume no responsibility), I won't state the details here unless there is expressed interest.