How do you install WPMU Dev? (the system needs a bit more detail so see below)

Hi,

I want to install WPMU Dev on a second domain. I have a working WPMu Dev site through which i can ask you questions with my account.

But I can not find anywhere a step by step process for installing the WPMU Dev dashboard.

I uploaded what I think is the dashboard (it seems to be called wpmudev-updates)

but it isnt appearing in the plugin page of my new site, so maybe I am doing something wrong. As I cant see any documentation I cant go back to see how I did it last time. It is definately in the right plugins folder in the right location... that is where my other site's updates plugin folder is.

Can you help please?

thanks