Newtrix doesn't work on my 5.2.0 Paperwhite, but gmplay does. So if the international k5 is "almost" 5.2.0, perhaps newtrix fails on it and gmplay works too. We are close. I just need to backport the gmplay GMLIB to newtrix.
I wish they would stop
fscking with the eink ioctl stuff with minor firmware updates.