Yah this isn't a small undertaking. It works with FFXI but unless you want to manually register all the DLLs (and know how) you need to grab a command line script someone wrote to register the DLLs. As far as I know no one has written a script yet for FFXIV and I wouldn't know which DLLs would have to be registered. The other bit...backing up the Square Enix folder in Program Files and the folder of the same name in your My Documents folder and backing up the FFXIV registry keys...isn't a problem. DLL registration can be.