I discovered an interesting issue while decorating an EventTopic subscription in my ModuleController for one of my modules. The decoration was like this: [EventSubscription(EventTop... ThreadOption.UserInterface)... void OnMsgReceived(object sender, EventArgs<Msg> ev) The event is fired on a non-UI thread, and I disovered this event handler was being called on that thread, NOT on the UserInterface thread as specified in the decoration. This decoration works fine in a ......