Yeah it's not a virus, I don't even know how to make virus' or apply them to shit... and I would never fucking do that... LOL I have some morals, not everyone on the internet is a degenerate asshole.
And yeah I should of included a guide but basically you just re-name it to whatever your current save file is on DBD... best thing to do is boot the game up so it makes a save, then locate the folder like you've explained and that's it...
It's a good thing the programming on this game is so shitty, that beta version literally was just a capped off full version of the game, they basically didn't change a fucking thing and didn't fix anything... RIP game. I've already gone through like 5 million bloodpoints just trying to rank up a couple survivors to 50... good thing I prestige'd all of them before I made a back up of that save... it makes the survivor side a lot easier to deal with, the killers are too OP right now.
And you're welcome.