it's on their forum, now it's their problem what they do with that
and if they put some fixes in the esm, that is in the same state, instead of replacing update esm
you just compare their old esm to their new esm
copy paste the conflicts in a patchx esp
and after checking it look right in the log, and in tesedit, use it like that, or put it in update or skyrim esm
if that esm is clean, you just use it like that (after checking some of its conflicts with old esm of course)