Don't worry mate, take the time that is necessary, it is already very big what is achieve with the application in the actual state, if I find more problems I will keep reporting it in the github.
And seriously, thank you very much for the tool and the time you are dedicating to it.
OK, I'm pretty close to a solution on this finally.
There's actually at least 3 separate problems:
I've worked around this with a hack for the first issue and rebuilding the Fatdown bundle in s9e/textformatter with support for HTML headings and entities.
However there's still an unresolved <div> tag in the earlier example post I've been using to evaluate this so I feel like there's still a fourth one. But I just wanted to say I hadn't lost the plot on this entirely and the next iteration of Porter will fix at least most of the problems.