title: Custom Wix Burn bootstrapper doesn't detect MSI install state
body: <p>I'm creating a custom wizard-style bootstrapper based on Wix/Burn (3.6 release version). I've based in on the Wix 3.6 bootstrapper code. </p>
  
  <p>The problem is that I cannot get the bootstrapper to detect the install state of my setup.msi that is part of the bundle.</p>
  
  <p>As I understand it, all that's required is to call Engine.Detect(), where Engine is an instance of the Wix Engine from the Bootstrapper Application. At that point I should be able to look in Bootstrapper.Command.Action to see what the required launch action is.</p>
  
  <p>My bundle contains two items: .NET 4 (web install) and my setup.msi.</p>
  
  <p>I suspect that I'm missing a step to determine whether I should put my wizard into maintenance mode vs. install mode.</p>