Yeah, I could add a SpeakString() call in there, but this guy isn't your normal bard strumming a harp - its an automaton, so the lack of a verbal response fits.
EDIT: Opted for SendMessageToPC(GetLastSpeaker(), "The object is busy and can not talk to you right now.");
Sends the generic yellow highlighted message over the server channel. I can also configure the script to search the tag of the caller and use SpeakString() to do customized responses. Since its a generic OnConversation script, it need to be nonspecific.
And yes...I'm having tons of fun reverse engineering the X2 Ambient System and adding my own features to it. Nereng's guide is proving invaluable in helping me tailor the system to my needs.