wal-g configuration

Hi,
I am trying to test wal-g setup (ubuntu 18.04 and postgres 11.7) and am
having a hard time configuring wal-g with encryption.
Documentation on
https://github.com/wal-g/wal-g/blob/master/PostgreSQL.md#configuration is
very basic and doesn't give detailed examples etc on setting up encryption
for wal-push/backup-push/wal-fetch/backup-fetch.
Wondering if there is a more detailed documentation that I can follow on
how to set up the environment variables for PGP.
Everything works fine without encryption.
It lets me encrypt using WALG_GPG_KEY_ID but decryption fails complaining
that this is a deprecated option.
So, I have to use PGP options.

I am testing on ubuntu 18.04 and postgres 11.7.

# cat WALG_PGP_KEY
asadtest
# cat WALG_PGP_KEY_PATH
/etc/wal-e.d/env/pub.key

NOTE: pub.key just contains the actual public key in it.

This is what I get when I try to run backup-push:

$ envdir /etc/wal-e.d/env/ wal-g backup-push
/home/postgres/pgdata/pgroot/data
INFO: 2020/09/18 19:46:20.474918 Doing full backup.
INFO: 2020/09/18 19:46:20.495627 Calling pg_start_backup()
INFO: 2020/09/18 19:46:20.631805 Walking ...
INFO: 2020/09/18 19:46:20.632116 Starting part 1 ...
ERROR: 2020/09/18 19:46:20.632164 upload: encryption error openpgp: invalid
argument: no armored data found

Appreciate your help on this.

Regards,
Asad