Option 1
We start in the normal world and manually manipulate the files when it is time to start so that everyone logs out and back into the new UHC world in their random starting location. This is a good solution but the problem is that sometimes the spawn doesn't happen right and you end up WAY high in the air, inside solid object, or something similar and end up dying right off the bat. If that happens, then the person who dies will end up at the world spawn point (which is obviously not random). Then either we 'reset' that person's files, they log out and back in again until they get a good spawn point. Problem is everyone else is waiting while this is happening, and could die themselves. We could give everyone god mode for that time period to combat this.