Your First MP in XML
This is a very old tutorial I wrote that is a good first step into the intricacies of XML authoring for SCOM. This talks about how you set up your XML editor pointing to a schema and then walks you through a simple class definition and discovery from the registry. This is likely very old for a lot of you but this is still where a lot of people start. Yes you can do all this through the authoring console today but the purpose of this tutorial was to introduce you to the XML level and it was written at a time there was no authoring console.