I know this can be very frustrating when things go wrong.
in the situation though , apparently you did not understand that there are two versions of the update. one is the autoupdate version and the other is the full package.
the autoupdate that you have probably been using all along does not work properly for the 3.1 to 3.2 upgrade ( not update, upgrade ).
should they remove it? I think so. the full package and file replacement that was mentioned several times in this topic works pretty much perfectlly everytime when done properly.
you can't get messages about merging files etc. you just get the update tab and when you click on it you get the update screen telling you to update the database only.
that is it. it works for thousands of people all of the time.
If you decide to try it again, follow the instructions below exactly and in order and I bet you a nickel it will work the first time.
https://www.phpbb.com/support/docs/en/3 ... upgrade31/