If you're not sure which keyboard definition to download, I recommend that you use the New Zealand Māori (Alt) Keyboard Layout.
Once you've downloaded the keyboard definition you want, proceed to the Setup Instructions to install and configure it.
Legal stuff
These keyboard definitions are released into the public domain.
This means that anyone can use, redistribute, modify or extend them free of charge.
No warranty or guarantee is provided - use at your own risk.
New Zealand Māori (Alt) Keyboard Definition
Macron characters are generated by using the [AltGr] (Right Alt) key in combination with the vowel.
New Zealand Māori (Combo) Keyboard Definition
Macron characters are generated by using either the [~] then Key combination or by using the [AltGr] (Right Alt) key in combination with the vowel.
New Zealand Māori - International (Alt) Keyboard Definition
This keyboard definition supports macron characters, as well as the European accented characters - very useful if you're working in Europe.
Macron characters are generated by using the [AltGr] (Right Alt) key in combination with the vowel.
This means that the [AltGr] + Key combination can't be used for the European characters, so these have been shifted to the [~] then Key combination.
Download the New Zealand Māori - International (Alt) Keyboard Definition
Keyboard Layout Source Files
You don't need these if you just want to use the keyboard layout.
You are free to download and modify these layouts.
These keyboard definitions, and their installers, are produced using the free Microsoft Keyboard Layout Creator, which you can find on the Links page.
Download the New Zealand Māori (Alt) Keyboard Definition source file
Download the New Zealand Māori (Combo) Keyboard Definition source file
Download the New Zealand Māori - International (Alt) Keyboard Definition source file