[quentinp]

I cannot thank you enough for the work Bruce Miller, you and others are doing on LaTeXML.

However, LaTeXML is not 100% feature-complete at all (sorry if this is not what you were saying). For anybody not knowing how to improve LaTeXML itself (eg. by adding support for missing LaTeX packages), the only way to get it working is by using it from the beginning to avoid using anything that would not work out of the box in LaTeXML.