Search notes:

Registry: HKEY_CURRENT_USER\Software\Microsoft\Office\X.Y\Word\Data

The HKEY_CURRENT_USER\Software\Microsoft\Office\X.Y\Word\Data registry key stores most recently used lists, such as

In additon, this key also stores settings about

The data is stored in binary format.

Settings

Settings is a binary value that seems to store the options (such as auto correct, spelling settings etc.)

Since the value is binary, its at best difficult to change the settings directly in the registry.

However, they can be changed with PowerShell.