Hi Michael,
Running the install script as sudo will most likely have created the temp/working folders as sudo also, which of course would have an impact if you later start the server.js as a non-sudo user.
I'm not sure why you received errors during the installation, but this could possibly be because you installed NodeJS or npm modules as sudo. If you have done this, you will most likely have problems with any NodeJS application.
This link might be of some assistance:
http://www.johnpapa.net/how-to-use-npm-global-without-sudo-on-osx/
Regards,
Brian