Well, that is definitely very unfortunate. I start out with a URL, so I don't have an ebook to begin with. If I use FFF-CLI to make the ebook, I will have to import that and then somehow manipulate Calibre to replace the cover, manually assign all the custom columns and more of that mess... and probably still break interaction with using FFF from the GUI when I do want to use it from there. (Not to mention the problems involved with having two workflows trying to do the same thing.)
I guess I have to find some other way to go about this.
(When I saw that FFF supported CLI and all the parameters it supported, I had not expected that this of all things would turn out the be the most troublesome issue to tackle!
)