#2 by FantasyFan - Jul 11 2011
First off, you need to be on Ellen's path (either friendship or romance). If she starts confiding in you about how frustrated she is with her family and how she wants to do scientific research that involves magic, you're on her path.
Now I'm not SURE about this, because once I played through her path and got her invite to the conspericy, and once I didn't, but I THINK what you have to do to get invited to the conspericy is NOT encourage her to run for treasurer. When she talks about William, suggest "Tell him you like him" instead of "Wait and see" (because "Wait and see" will get her to run for treasurer). Now this is all speculation, because the first time she didn't run and I got invited to her conspericy, but the second time she became treasurer and she didn't. I THINK that when she becomes treasurer, she has a better relationship with Professor Grabner and thus won't want to do things behind his back, but that's only speculation.