The zxp package is basically a zipped directory.
1. Rename the .zxp ending to .zip
2. Extract or Unzip the .zip file
3. Copy the ''LTTR.INK.AdobeIllustrator.aip'' file from the extracted directory to "C:\Program Files\Adobe\Adobe Illustrator 2022\Plug-ins\"
The plugin should be available in Adobe Illustrator after that.
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