Modifying a model involves editing the xml files with any xml editor you find comfortable (including Microsoft's XML Notepad, or Ethea's own Instant XML Editor), or changing the model building code and running it again. In the future, we will provide an interactive tool for those who like the RAD approach more. Please note that running the model building code will destroy any changes made to the xml files. Model building code goes into a model builder, a unit usually compiled in a Plugin. See this section for more details about creating model builders.