Debugging custom actions in a Visual Studio 2008 installer

It's simple. Just add the following:

public override void Install(IDictionary stateSaver)
{
Debugger.Break();
...

In order for this to work, I also had to (obviously) build the installer in Debug mode and make sure that Debugger.Break was the first statement in Install(...). This article was really helpful http://harriyott.com/2007/02/debugging-custom-actions-in-visual.aspx