These codes are a part of one of my blog series. The series name is "Data Validation Series: Excel-XML-XSD-VBA The Holy Rectangle". You can find this series on both my personal web site and my Medium profile.
Here are the links for the blog series from my personal web site: http://efebuyuk.com/data-validation-series-excel-xml-xsd-vba-the-holy-rectangle/ and Medium profile: https://efebuyuk.medium.com/data-validation-series-excel-xml-xsd-vba-the-holy-rectangle-8028d7071181