Hi,
I'm very surprised at your defensive tone and I'm quite at loss to see where you took offence! I asked some reasonable questions and I provided you with, I would think, helpful feedback. Are you the moderator for this forum? Do you decide what is discussed here? I apologise on all counts though - and don't worry I have won't be discussing your plug-in any further.
Anyway, your theme part of your plug-in is clearly a halfway substitute for Luther, since it takes over the interface, has a different footer and header php file etc., I can see now some of your reasons for this but I think it would be more elegant to avoid it, by simply incorporating it into an updated Luther theme which becomes the basis of you specilised type of PressBooks, I'm not an academic and I can't offer work for free but I am working on and interested in technical and reference collaborative workflows, so the tools you've cleverly developed were interesting to me.
I have told you twice that there is a serious issue with your plugin breaking permalinks through all the books. regardless of whether the theme is activated as well. I was looking into a solution but I thought you might like to know - I have actively developed some extras and found some bugs in the PressBooks plugin from early on and I've created a Github pull as requested - so I do try to help.
It was an innocent question: if you're behind the DOCX import and PBLatex then I congratulate you. My confusion was they were already there before I installed your plugin and I was keen to know if it added some extra functionality.
Peace