Simply open the downloaded zip file and extract to your location of choice. Make sure you computer meets the minimum requirements listed on the download page.
From the main screen, select the spanner and screwdriver icon on the top right. If this is your first password just leave the 'Old password' box empty.
You can but we don't recommend it. To remove the password simply enter a new password of 1234. This is the default password and will stop the app requesting a login when you open it.