In supplementalMetadata.xml is a list of macrolanguages. Each line must specific a mapping from the predominant encompassed language to the macrolanguage. The macro language mappings are on:
Be sure to also change the comment if making a change, otherwise it will be misleading.
In the above example case, the "most predominant" form is "lbk" (Central Bontok) with the largest population. The resulting line in the XML file would be:
<languageAlias type="lbk" replacement="bnc"/> <!-- Central Bontok => Bontok -->