When posting to the forums please could you be clear whether your question relates to the authoring tool or framework and please list versions where appropriate.

It's also useful to know what platform you're on (Windows/Mac/*nix), what you've tried so far, what instructions you're following etc.

For example, one of those most common problems people run into in the installation process is to use the wrong version of NodeJS - but if you don't tell us what version you have installed we can't check if that's the case.