I am trying to customize my installer accordingly, so that it looks, wether there are specific folders in the $INSTDIR, which is getting set on a MUI_PAGE_DIRECTORY. If it finds these folders, it should compress them and put that archive into a backup-folder under $INSTDIR and set it's name according to the date.
I have searched long to find a solution for this, but I did not find any compression plugins nor did I figure out how to ship a 7zip with it and use that for compression. I am not as fit with NSIS though.