Open document format is big and ugly, so ooffice.4ht is also big and ugly. If you want to better understand, what is going on, you must understand some basics, which are described in resources posted in your post.
ooffice.4ht also add some custom macros, useful for dealing with styles. There are two types of styles used here. One are defined in file with text content, an they are configured like in the answer about inconsistent footnotes:
\Configure{automatic-styles}
{\csname a:footnote-style\endcsname}
\NewConfigure{footnote-style}{1}
\Configure{footnote-style}{%
<style:style style:name="Footnote-text" style:family="text">
<style:text-properties fo:font-size="10.0pt" />
</style:style>
}
With \NewConfigure{footnote-style}{1} you are declaring new configuration footnote-style, with one parameter. With \Configure{footnote-style} you declare the style and
\Configure{automatic-styles} is inserting call to the declared configuration footnote-style. You must use internal name a:footnote-style, this is created automaticaly by NewConfigure.
Other style macros are \NewConfigureOO and \ConfigureOO:
\NewConfigureOO{textul}
\ConfigureOO{textul}{<style:style style:name="textul" style:family="text">
<style:text-properties style:text-underline-style="solid"
style:text-underline-width="auto"
style:text-underline-color="font-color"
/>
</style:style>
}
These configurations go to the settings.xml file. I don't know what is the key about what styles belongs to styles.xml and which to the content.xml, you must find that in odf documentation.
Other parts of that file deals with command redefinitions for inserting configurable hooks and providing xml configurations with these hooks.