Thinking about what you are trying to do, you might be happier with the content server or an calibre2opds catalog.
First, I assume that you have a LAN at home that you will use to push books around. My thought is that instead of pushing books to your clients (family), instead they pull the books they want to read. Either the content server or calibre2opds-generated pages would do that. Your family member decides to read something. S/he goes to your server (either http:// if you are running a content server, or file:// if you have a network share with the library on it), browses, finds the book, and downloads the right format to the desktop. Then fire up the right reader, import the book, and they are good to go.
There are several reasons this won't work (no lan, no network storage, etc), but maybe it solves your problem?