I found a bug in the VB sample code related to creating sub triggers.

From the original source (SampleTriggerType.vb):
Code:
Protected Overrides Property SubTriggerTypeNames As List(Of String) = New List(Of String) From {
    "Button click with X options checked",
    "Button click with specific option checked",
    "Button click with no options checked",
    "Button click with any options checked"
}
This fails at runtime. The value for SelectedSubTriggerIndex won't be correctly set.

Changing the definition to this fixes the problem:
Code:
Protected Overrides Property SubTriggerTypeNames As List(Of String)
    Get
        Return New List(Of String) From {
            "Button click with X options checked",
            "Button click with specific option checked",
            "Button click with no options checked",
            "Button click with any options checked"
         }
    End Get
    Set(value As List(Of String))
    End Set
End Property
I hope this saves somebody the couple of hours of troubleshooting it took me!