All I know about HP is what I've seen in the first two movies. Saw the first one when it came out, and the second one last night on the tube. From my hazy recollections of the first one, and what I saw last night, I do not want to see a HP RPG.
As far as I can tell, JKR wants to teach kids three things:
1) Never tell any adult anything important.
2) Especially never tell any adult in a position of authority anything about any crime you might know anything about.
3) Make absolutely sure that if you have a clue to a murderer's whereabout, that no adult, especially any in positions of authority, can do anything about it. Instead, go and confront him yourself!
As far as I'm concerned, she's a menace to society and shouldn't be allowed anywhere near children.