Where are the contrib plugins?
The contrib plugins setting seems to be missing, you can't add Slack or Hipchat integration in the settings like suggested here: http://taigaio.github.io/taiga-support/contrib-plugins/hipchat-integration/
Could it be the readonly conf.json? Ok I just checked, there is no plugins folder anywhere. Do you think it's possible to include the contrib plugins in the next update?
To upload designs, you'll need to enable LFS and have admin enable hashed storage. More information