Make it possible to add conditions to events, e.g. only allow event foo, if condition bar is True. I'm not sure, how this should look like. Some static conditions could be "key pressed == a" coupled with "key down" event. Conditions could also be coupled to controls via registering the control reference like dynamic events. If my idea Expand Event structure functionality: Register new types of references is realized, a condition could also be something like "tcp/ip connection is offline". If a condition is not fullfilled, than either nothing happens or there is a leftside node, which indicates the status of the condition. This should be configurable.