I did this for Afrikaans, that spreadsheet is completely outdated in my experience. You should try emailing them directly and ask if you can help add it. In general what you need is to write a grammar guide, find online dictionaries from English to Maori, other languages work as well of course. (adding Afrikaans was a pain and the dictionary integration was the most important thing there) Then you need someone to translate the mini stories into Maori and make corresponding audio files of them.
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