Hi Richard,
I have been able to replicate your issue by using node version 0.12.0. In our production environment, we are using node version 0.10.33, as this is the highest version that we have fully tested across.
I have recorded the issue in github, and we'll work on a fix for that as a priority, but in the meantime, I recommend using version 0.10.33.
You can use nodist if you've installed on windows. Instructions are here. Otherwise, you can use nvm.
I'll update this thread once we have tested against node version 0.12.0.
Dennis