dita4publishers | Version 1

The reason the numbered chunk HTML file is generated is because the topichead element does not (and should not) include a filename. When a chunk attribute is added to the map, pubmap or bookmap references, the filename is taken from the name of the .ditamap file.

I've tried your examples here and both of them worked for chunking content if I used the D4P XHTML transformation or a variation of it. So there's nothing wrong with the DITA XML you're using, just with the old HTML 2 plugin. You probably need to switch to either the HTML 5 plugin or the XHTML plugin. The HTML 2 plugin is no longer developed and only included for legacy users.

You've described the problem incorrectly. In terms of the XDM data model, you don't want to "remove a namespace" from the output, you want every element in the output to be in a different namespace from the one it is currently in. (Specifically, you want it to be in no namespace). That affects every instruction that creates an element. So the easiest way to achieve this is probably by a post-processing pass on the current output, changing the namespace using the template rule

You can either set the chunk attribute of your element to the value to-content or call your DITA-OT transformation with the parameter -Droot-chunk-override=to-content.

You seem to have two use cases: 1) Customize the HTML output produced for each topic. 2) Customize the HTML output produced for the index.html table of contents.

By answer will be mostly about (1). Once in your plugin.xml you add this extension: