I reported this before, when I transfer my Xbox one world, which has like 85% of the Xbox 360 part used, to the bedrock version, it hits 3% or 4% and crashes, I reported this back on 1.2.3 and it still does this in 1.2.5, Mojang, it has been long enough, this bug has happened since the beta and is still not fixed, sure coordinates are cheats and stuff, but please fix the major bugs first, if you can't transfer your world's, then people will stay on the old version and the new version would be completely useless.