Are you getting an error message? Did you use a mod previously which is no longer being used? The only issue I've seen people have with it not loading is because they used the SanchoMod that is no longer updated. The error message has a bunch of "OOO000OO0OO" type stuff in it, which is the marker that denotes it as Sancho's work. If that's your issue, you can either start from scratch with a fresh save, or you need to get the save fixer from the mod thread's OP and put that in the folder of every update going forward.