You need to modify each category... then you need to move all the links.
This is a problem in the software. No good way to make updates like this.
You might as well edit the category.db directly, and then go move the links... You might be able to get by, if all you are doing is changing /Employment/ to /Jobs/ to do that in both your links.db and category.db then rebuilding.... check your links for any orphans later, and make sure the replace is unique, or do it by hand.
I've done all sorts of things like this trying to get started.
There are no 'index' files to get corrupted, as long as the category field in the links.db matches a category field in category.db the files will show no errors...
Good luck
