The sample theme suggested by the official documentation doesn't work

Hi,

[running ironwood.master, fullstack]

I’ve followed this official guide to installing a theme.

The first thing that a newbie in theming will do is to install the example theme suggested by the documentation:

The problem is that the sample theme is obsolete and deprecated, and installing it will throw errors as soon as the user clicks on the link to show available courses. It is a known error:

# tail -f /edx/var/log/lms/edx.log
AttributeError: 'CourseOverview' object has no attribute 'start_datetime_text'

Reported some years ago.

Moreover, if I try to update the assets of the theme, following again the official docs, it is suggested to run this command:

python manage.py update_assets

But it is not working (or I’ve misunderstood how it is supposed to work):

edxapp@edx-mooc:~/edx-platform$ python manage.py update_assets

usage: manage.py [-h] {lms,cms} ...

manage.py: error: invalid choice: 'update_assets' (choose from 'lms', 'cms')

On the other hand, if I run this (equivalent?) command:

edxapp@edx-mooc:~/edx-platform$ paver update_assets lms --settings=production

I get a an error here:

...
 File "/edx/app/edxapp/venvs/edxapp/local/lib/python2.7/site-packages/sass.py", line 644, in compile
    raise CompileError(v)
CompileError: Error: File to import not found or unreadable: lms/static/sass/partials/base/variables
       Parent style sheet: /my-open-edx-themes/edx-platform/example/lms/static/sass/base/_variables.scss
        on line 1 of ../../../../my-open-edx-themes/edx-platform/example/lms/static/sass/base/_variables.scss
>> @import 'lms/static/sass/partials/base/variables';
   ^

Build failed running pavelib.assets.update_assets: Subprocess return code: 1

I don’t know if that error is because the template is obsolete or because the intended command was python manage.py update_assets and I have executed this other one instead paver update_assets lms --settings=production

UPDATE: it has been also reported in this tutorial.

Any help about the correct way to install a basic, updated, working theme, will be greatly appreciated.
Perhaps it will be suffice to link to an updated sample theme from the official guide (or warn about potential problems if following the outdated sample theme)

Thanks.