A few weeks ago, I met with Don Rosa, too (he was visiting Finland), and was really nervous. However I didn't really need to, since there was a long line and thus I couldn't speak with him other than greetings, asking for signing and thanking him. (haha...)
You were incredibly kind the time I met you at Youmacon! Not a single moment of a bad impression. Even my fiance, who hadn't known about you beforehand, thought you were incredibly polite and wouldn't mind meeting you again.