Okie dokies :3 Takes my laptop about 20 mins just to open that version, haha. Got there in the end though :D
I guess you should probably make a backup of your save files first + put them somewhere safe. Then you'll want to grab both of the files in this folder. Put em in your game folder where the .exe is + overwrite your versions of the files that are in that folder.
When you load the game, you'll see 3 saves. It's the 3rd save that you wanna load to continue from where you were in the game and avoid bad end 12 :3
I don't know if you've been following the walkthrough or not, but if so, you'll know that there are 3 required bad ends in the ??? route to be able to unlock all of the final endings. I didn't know how many of those required bad ends you've seen, so save 1 is just before the first of the required bad ends in case you hadn't viewed them all and wanted to.
Save number 2 is at a place where you can get stuck at bad end 14 if you haven't viewed the 3 required bad ends of the route. I just left you a save there so that you can view that bad end if you want to. (Don't look at it first though, as it's quite a past the point where you were stuck before so it has spoilers/won't make sense until you've played more from where you last left off.)
And yeah, like I said, save number 3 is the one you wanna load first cos it should be where you left off :3 I already got you the 3 required bad ends on that one, so you should be able to eventually get to see all of the final ends from this save without having to go back and do anything else :D I suppose to be on the safe side, if you wanna make more saves as you play, make em in save slot 4 and onwards rather than overwriting anything in slots 1, 2, and 3.
Oh, and there will be some stuff unlocked in the gallery from sections of the game that you haven't seen yet, so maybe don't look in there until you've played through some more if you wanna avoid spoilers, haha.
Hope it works okay for you :3