2.1.282 Part 1 Section 17.9.12, lvlText (Numbering Level Text)
a. The standard does not bound the number of escaped sequences %[1-9] included in the val attribute.
Word allows at most 9 escaped sequences %[1-9] in the val attribute.
b. The standard allows any length string for the val attribute of lvlText.
Word requires that the length of the val attribute be at most 31 characters after instances of the % syntax are converted to their final values.
c. The standard states that if the val attribute contains a % followed by a number higher than the current level, then that number is ignored.
If the val attribute contains a % followed by a number higher than the current level, then Word ignores the entire lvlText.
d. The standard allows the val attribute to be omitted while the null attribute is not set to on.
Word requires that the null attribute be set to on if the val attribute is omitted.