Unfortunately it appears the keys are worthless. The source code is also for the Xbox One Bootrom. The Source code might have some useful things to it but the keys won't amount to much.
I got WinPDF for testing before they removed it. SM64 worked fairly okay-ish with some slight slowdowns, input lag and minor graphical issues. As far as I can tell it has been removed from the XBL marketplace and still does show up and work on my Xbox.
Finally noticed this thread. I was playing the beta quite a bit on PC along with a couple of friends. Although i'm probably gonna wait for awhile until I buy this game since what's in the Beta is what will be available at launch. Blizzard said they're actively working on new content so i'll...
If you want Minecraft mods, i'd recommend getting Tekkit. Also using Shader Mods if you want dynamic lighting and stuff like that but it is pretty GPU heavy so keep that in mind.
Sorry for the late reply but try using XTAFUSB rather than Party Buffalo.
Also, you don't need a flashed console to play demos from USB. If you wanted to play full games that you didn't purchase, you would be a RGH/Jtag console but since they need demo help, they don't need a modded console.
They're having a really good sale on games over at humble bundle right now, too. I was able to get Overlord 1/2, Skullgirls and Rogue Legacy for about 10.50USD
If you're using a low quality disc for the burning that could cause the issue or if you're burning the discs too quickly. Only other thing I can think of is your DVD drive is going out so the burn is sloppy.