Hi,
Support for this variety of markup is not a feature of the HtmlToWmlConverter module. It could be possible to enhance that module to support this variety of markup, but this is not on the list of things in the near or medium future for me. You could certainly enhance the code to support this, but you would need to be familiar with writing Recursive Pure Functional Transforms (RPFT) in C#. See the following screen-cast series.
Recursive Pure Functional Transforms Series
Probably would be easier to directly change the markup.
Are you familiar with the HtmlAgilityPack:
https://htmlagilitypack.codeplex.com/
It is a good C# API for doing this variety of stuff.
Cheers, Eric