I was scavenging around on my old computer today, and the last time I had played Minecraft on it was in Alpha. I found one of my old worlds that gave me so much nostalgia. Yay! So I put it on my USB drive and transfer it over to my new, overpowered computer. I put it in the saves folder in .minecraft, and loaded up Minecraft. I looked for the world. It wasn't there. I tried deleting it from the saves folder and the USB drive, and transferring it again. Nothing. I thought that maybe I would just have to play it on the old computer. Nope, 10 fps. Anyone have any ideas?