Hi,
I personally would like very much if Update Manager could handle list of files what is modified and keep them safe in update.
Samekind filemanager as Akeeba Backup "Files and Directories Exclusion" would do that job very nicely i think.
So in future if theres any need to modify some file, it just tag in filemanager "do not touch" and update process can handle that by it self.
But thank you in nice component anyway!
Br, ilDirty