Im not sure what 3 buttons on boot means. I have a TWRP backup of another tvonline 4 to work with. I got rid of the majority of the errors using twrp to change the unmountable partitions to FAT then back to ext4.
Then I repaired filesystems of the unmountable partitions.
I uninstalled supersu.
I restored the backup from the other Tvonline 4.
Now the only error I get is
AVOV logo
to system recovery
reboot system now,
apply update from EXT
apply update from cache
apply update from ADB,
wipe data/factory reset,
wipe cache partition,
reboot to bootloader
power down
view recovery logs
dead android
Recovery is listening adb sideload...
Waiting adb sideload command...
Cannot load volume/misc!
There was a post last year where a few people had the same cannot load volume/misc! error after upgrading to 1.06. There was a file that supposedly fixed it, but there is no trace of it on the post.