This fork has an additional function which allows one to automatically fix the cases of filenames and foldernames on windows so that they match exactly with what is present in Calibre's database.
This isn't useful at all if you are only working with Windows, but if you would like to be able to copy/sync your library to a posix filesystem that is case sensitive then it is extremely important that the paths match what is in the Calibre database exactly.
> Quality Check > Fix > Check and re-case book paths
The operation is idempotent, that is to say running it again will leave the library unchanged if no new files have been added.