uninstall gnome-do plugins
Did you try purging (remove package files and configuration files) both gnome-do and gnome-do-plugins packages and then reinstalling gnome-do ?
sudo apt-get --purge remove gnome-do gnome-do-plugins
.. followed by ..
sudo apt-get autoclean
Then try reinstalling gnome-do. That should simulate a fresh install of gnome-do and hopefully remove this issue.