I believe the 8.41 announcement indicates what there is to upload from the download if your going from 8.4 to 8.41
There is no upgrade or xml stuff that needs to be done.
Basically there may be a changed template here or there for Xenforo but 8.41 continues where I left off with 8.4. I have carried over the templating work I did with the standalone and xenforo and cleaned up the templating for the forumstyle as well as vb4 and vb5 as well as fixing what vBulletin broke with there 5.03 changing there entire styling.
We are not setup to offer incremental downloads which is why we offer detailed announcements on what has changed.
Basically you want to upload the core files noted your integration file as noted and the languages and templates folders.