Consider the following line in config.yaml (master branch)
gems_install_path: "/root/.autoproj/gems"
Should it not point to the user's home directory?
With root/, gem installations fail; one would be required to call ./install_esrocos with sudo.
I manually changed it to /home/taste/.autoproj/gems (in the TASTE VM) and worked.
Note that gem does not like the ~ in paths...