First, you'll need to sign up for a Player.IO developer account here: https://playerio.com/register.
You will need to create a new game from the dashboard, so follow the Go to admin panel link after logging in and click on the Create New Game button. Copy the game ID for later, as we'll need it for connecting.
Next, download the developer package, which contains Flash and Unity client SDKs, and the development server: https://playerio.com/download/.
After downloading and unzipping this, navigate to the Flash folder and copy the
NewGame folder. Paste this wherever you like (I usually paste it into the same directory) and rename it, then delete the
Flash folder inside. Now, you can open the SLN file to begin ...