I'll post what she says, as for some reason she can't register to the forums:

"How to save time downloading
How to avoid the download of Steam's old version and all the new patches and updates If I have already the folder copied and pasted in a new hard drive ... I am asking this because my main hard drive where I had FFXIV installed died today. And I want to avoid the wait and download all over again from Steam and Square Enix subsequently. I was wondering if there is some way to do this and play by executing FFXIVboot.exe

Thanks in advance"