i *still* don't understand how this onlykey works. i've kinda figured out how to generate subkeys (you have to have $GNUPGHOME point to a valid keyring that has a public key on which you want to create a subkey for, but use `--homedir` to point to a new directory for onlykey to put the new keyring with the subkey), but now it won't generate keys except for the uid i used to use?