This nonXML-Indexer is a server extension which accepts nonXML-documents of some types and tries to extract some content and metadata from these documents. The extracted information will be transformed into an XML document which is called a shadow document. Shadow document and original nonXML document can be stored inside Tamino. The generated shadow documents have a pre-defined structure. Schema templates that describe this structures are delivered with the server extension. Changing the schema will probably lead to errors when storing the shadow document because your modified schema will probably not match the generated shadow document.
To use the nonXML-Indexer it needs to be installed first. In order to use it you need to define some schemas (see above). Templates for these schemas are provided with the Tamino installation, only doctype name and collection name need to be fixed. The schemas describe the structures generated by the nonXML-Indexer, they also define some indexes.
When using the nonXML-Indexer for a doctype then X-Queries and XQueries work on the generated shadow documents. To access the plain nonXML documents you need to use plain url addressing either referring via ino:id or via ino:docname to the document.
For further details, e.g. about the supported mime-types, please refer to the documentation.
Hope this helps. Best Regards,