I found solution:
Self.OnKeyNotify := @TContactDictionaryEventsHandler.OnKeyNotify;
instead of
Self.OnKeyNotify := TContactDictionaryEventsHandler.OnKeyNotify;
glad to hear you found this, and my apologies for the delayed reply — unfortunately the colleague most suited to help with this issue was off yesterday :(.
Please don’t hesitate to let me know if you have ay further questions.