1) Make sure your machine supports the .NET framework. If your Windows is up-to-date, it is probably there.
2) Install the SimpleAgent ActiveX by executing "regasm iao.net.dll /codebase". "regasm" is usually located at "C:\WINDOWS\Microsoft.NET\Framework\v2.0*".
3) Enter secret account id: (Copy value from the account settings page).
4) Agent Running. You can toggle alarms and check out the source code.