Worlds don't convert properly from 1.13 Pre-8 to 1.13 Pre-9 (MAC OSX)

Crash report is attached. 

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Main problems:

This only happens on SOME worlds which appear to have edited chunks. Other worlds like a new world made in PRE-8 and then immediately up-converted (with no editing done to any terrain) to PRE-9 do work.

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Description: Exception ticking world

java.lang.IllegalArgumentException: bound must be positive (At multiple places see full crash report attached)