I too have spent most of the day trying to go from OpenElec to LibreElec without success.
Copied the tar file over, rebooted and just got a screen full of colour. Red, yellow, blue and green.
Tried the SD-Creator same result.
Added boot_delay = 1 in config.txt, same result.
Using a Raspberry Pi model 2.
Any idea why I just have a screen full of colours and no boot up?