Basically, TKLBAM fails with the gdocs backend but I've almost managed to get it working by installing new versions of duplicity and python-gdata. But not quite... read below for where where I'm at. Please note that there might be some discrepancies in my description as my terminal scroll buffer filled up and as I've tried quite a few things and am going on memory I had to retry things which may have yielded different results to the first attempt given all that went on before!

So... in the beginning I downloaded my profile for my turnkey-wordpress-13.0-wheezy-amd64 virtual appliance (running in VirtualBox) from the HUB using

tklbam-init API-KEY

Backed up the downloaded profile from the registry, and copied the backup for possible subsequent modification:

cp -pR /var/lib/tklbam/profile /etc/tklbam/hub-profile

Then created a custom profile using the hub-profile dirindex.conf:

tklbam-internal create-profile /etc/tklbam/nonhub-profile /etc/tklbam/hub-profile/dirindex.conf

Then disconnected from the HUB (--solo) and loaded my custom profile (--force-profile) just created into the registry (/var/lib/tklbam): 

tklbam-init --solo --force-profile=/etc/tklbam/nonhub-profile

So far so good, but then when I go to make a backup:

tklbam-backup --address gdocs://USER:PASS@gmail.com/path/to/backup

Got this error

BackendException: Google Docs backend requires Google Data APIs Python Client Library (see http://code.google.com/p/gdata-python-client/).

and realised I needed python-gdata from the eror message and reading this so that Duplicity can support the gdocs storage backend. Found it already package for Debian so installed it:

apt-get update && apt-get install python-gdata

That fixed this error but then got a new error "'DocsClient' object has no attribute 'get_everything'":

# export PASSPHRASE=$(cat /var/lib/tklbam/secret)
# duplicity --verbosity=5 --archive-dir=/var/cache/duplicity cleanup --force gdocs://USER:PASS@gmail.com/path/to/backup

Backend error detail: Traceback (most recent call last):
[...]
  File "/usr/lib/tklbam/deps/lib/python2.7/dist-packages/duplicity/backends/gdocsbackend.py", line 182, in __handle_error
    raise BackendException(message)
BackendException: Error while fetching remote entries: 'DocsClient' object has no attribute 'get_everything'.

After some googling found someone who had a similar error so I thought that I needed a newer version of python-gdata. I tried these versions of the package 

python-gdata_2.0.18+dfsg-1_all.deb
python-gdata_2.0.18+dfsg1-2_all.deb

but neither of them fixed the problem.

So after further research here found out that duplicity probably also needed updating. Found out that wheezy-backports had this new version of duplicity backported so added

deb http://ftp.uk.debian.org/debian wheezy-backports main

to my apt sources (/etc/apt/sources.list.d/sources.list) and then installed it (forcing the release to the wheezy-backports release with the "-t" option  otherwise it won't be installed automatically):

apt-get update && apt-get install -t wheezy-backports duplicity

This still didn't fix the error but I then realised that tklbam runs its own version of duplicity!

/usr/lib/tklbam/deps/bin/duplicity

rather than the vanilla one

/usr/bin/duplicity

So backed up /usr/lib/tklbam/deps/bin/duplicity:

mv /usr/lib/tklbam/deps/bin/duplicity /usr/lib/tklbam/deps/bin/duplicity.v.0.6.18

and replaced it with a script which calls through to the backported duplicity (version 0.6.24-1~bpo70+1 in /usr/bin/duplicity) by creating a shelll script called duplicity in this directory (/usr/lib/tklbam/deps/bin) and making it executable:

cat >| /usr/lib/tklbam/deps/bin/duplicity <<'END'
#!/bin/sh
export PYTHONPATH=""
/usr/bin/duplicity $@
END
chmod +x /usr/lib/tklbam/deps/bin/duplicity

And voila tklbam-backup now worked!

Although, initially I did have a different error:

ImportError: cannot import name progress

since I didn't set 

export PYTHONPATH=""

which meant that python wasn't using the vanilla libraries but probalby those in /usr/lib/tklbam/deps/lib/python2.7.

In the longer term could a new version of tklbam be released either including or using the vanilla backported duplicity?

Thanks in advance!