Okay, so you want answers. I don't blame you. I would want answers, too. You know what, I'll give them to you; I have the time, unlike you. So, let's begin the story. By the way, I recommend reading this on a phone while you run.
I'm poor; there's no two ways about it. My PC isn't very new by any means, and I still own a square monitor. (Really though, who owns those anymore?) As a result, I downloaded lots of ROM files for the NES and SNES, as they were the only things I could run without lots of lag. My favorites were the classic Super Mario Brothers games, so I was quite happy when I found found a ROM I hadn't played. I downloaded it. I opened the archive that was downloaded. It contained two files: "Mario4.rom" and an emulator. I ran the ROM with the emulator that was included. The start screen read "Super Mario Brothers 4", and the background played the game's demo, which was the demo from Super Mario World. I pressed start on my gamepad.
I can't say what I saw. I simply can't. If I did, I would end up breaking every single rule on both Wikia and the Creepypasta Wiki. I can tell, though, about the cutscenes, if you could call them that. Each time I completed a world, a link appeared. I typed it into Google Chrome (BANDWAGONING!) and a black page appeared. Just as I was about the close the window, a livestream appeared. I don't know how I knew it was a livestream, but I was right. Two people in Mario character costumes were acting out scenes. Somehow, the video seemed to sync up with my progress in the game. That, everyone, is subtle nightmare fuel.
Once I beat the game, the computer cashed. (EDIT: On further investigation, it seemed that the ROM quickly displayed screens designed to push my PC's hardware. Neat trick, I guess.) I rebooted it, and went to check the ROM file. It had a new name:
LIVE.rom
I decided that this meant the livestream. So, wondering the meaning of this was, I opened the page. The video had become camcorder footage. The holder was running through a town.
My town.
I panicked. The holder came closer to my house.
I grabbed my pocket knife and hid in a closet.
I heard my door swing open.
I heard footsteps. Were they coming upstairs?
The closet door opened.
I ran.
As I ran, I cut the holder.
I leaped through the window.
I landed in the back of my truck, breaking my ankle.
I got in the truck and drove away.
The holder chased me.
I backed over the holder.
I heard snapping bones.
I saw the holder's broken body run into the distance.
I then returned into my house, bandaged by foot, then hobbled over to the computer. The livestream was still on, so I looked at it. The camcorder appeared to have been on it's side, with the road barely in frame. The video had lots of errors, too. I closed the window and went to delete the ROM before anyone else played it. It had a new name once more:
NEXT.rom
It just wouldn't delete, wouldn't go in the recycle bin. So, I did the sensible thing: Put the ROM on a hard drive and backed over it with my truck.
The website I got it from displayed a 404 error, and still does.
These answers may not be enough for you. If that's the case, well, too bad. It's all I know.