You use the Xchange 360 program and adapter to put it on the MU. That is why there can be several roster files on it.
It is actually like an image of your memory card and what it has on it. I still have my Xbox 1/PS1/PS2/Sega Genesis/Nintendo/Atari 800XL/Commodore 64/Colecovision/Atari 5200/VCS/Oddysey II!. Time to get a 360/PS3 Like the clown said on Seinfeld, 'You're stuck in the past, man.' Just kidding. Totally different game with different way of storing files, etc. All of my rosters update postings have been for the 360, so I forgot to keep posting that. Sorry, yes, it is a zip file made by xchange 360 for 360. Alot of people don't know how to put rosters on the MU for everyone anymore or at all, and a lot of people sold or put away their transfer kits. Unfortunately, alot of it is available online with Live, so those people without Live don't have access anymore. for putting the work in and sharing their rosters with us. I have a lot of respect for the roster makers like Knight, Goodfella/Paancaakes, Jason2112, DKrause, Neon 1, Tomba, etc. Someone needs to step up to the plate sometimes like in the old days here. Yes, I am glad to post these rosters when I can.