First step: Please confirm that the romiX rom is not booting up - make sure you remove the SD card before you boot the box. Just plug the box in and let it start. If it fails then go through the process to install remiX again - Demetris has provided a link to the remiX rom on page 1.
I'm not sure why the Libreelec boot didn't complete, but if Android doesn't boot it seems likely that is a big part of your problem.
The second thing is that you are booting an RC rom. Go into the SX2 link on page 1 and search out an appropriate 8.2.2 build. The file you download has to have the img.gz extension, not the .tar extension. "tar" is for updates only. I can't remember which build I used, but there is an 8.2.2 for the M8. If it doesn't work try a different M8 build, or perhaps the MXIII Plus 8.2.2 image. Always format the SD card between the builds you test. Don't forget the nocompat file. Try extracting it to the sd card. I have attached the remote.conf file - you can unzip this and add it to the sd card so that it loads when you toothpick boot the sd card.
I went through this process a couple weeks ago and was successful.