Doc. Section 18.104.22.168 describes the EventSequence responding to two types of triggers. The trigger causes the EventSequence to dispatch the next SequenceEvent. First, the trigger can be a Property. Second, the current Command can call:
"When calling unregister, the event sequence will get notified of this and trigger the next event if any."
I have found the first trigger type to work correctly. The second is not working in my implementation. The PendingCommandRegistry appears to dispatch the PendingCommandRegistryEvent.UNREGISTER event; however, this event is not consumed by the EventSquence.
Attached is a sample implementation.