[ic] PGP_KEY - what goes in here?

[Glenn McCalley]

I'd thought from the various PGP how to's in the archives PGP_KEY was
supposed to contain the specific key identifier within pubring.gpg to be
used, ID'd by the mailing address.
OK.
gpg --list-keys produces expected list of keys.
GPG "echo" tests work fine, encrypted output returned.
NOW!
Processing an order produces a gpg .err file that says

gpg: can't open glenn at bnetmd.net: No such file or directory

Changing PGP_KEY to any other value produces the same message, "can't open
<whatever>: No such file or directory"
That would seem to imply it's looking to open a file and there is none by
that name.  Looking for the keyring, maybe?
Changing PGP_KEY to /home/interch/.gnupg/pubring.gpg produces:

gpg: /home/interch/.gnupg/pubring.gpg: encryption failed: file exists

So -now- it's upset 'cause there -IS- a file by that name.
I tried the other values in the key entry shown by --list-keys as that
seemed to be indicated in the mailing list archives as a possibility but no
luck: "No such file..."

in variable.txt:
ENCRYPTOR    <blank>
PGP_KEY    glenn at bnetmd.net
PGP_CC_KEY    glenn at bnetmd.net
PGP /usr/local/bin/gpg --no-default-keyring --always-trust --keyring
/home/interch/.gnupg/pubring.gpg -e -a --batch -t -r 'glenn at bnetmd.net'

in catalog.cfg:
EncryptProgram    __PGP__
EncryptKey    __PGP_KEY__

in Route main:
credit_card    1
email    '__ORDERS_TO__'
encrypt    1
encrypt_program    "__PGP__"
pgp_cc_key    "__PGP_CC_KEY__"
pgp_key    "__PGP_KEY__"

All thoughts appreciated, much thanks.
Glenn.