Achievement Thread - Guide on how to achieve them

@arxtemis Sorry, I missed your post! Sorry for such a late reply.

I remember reading something about the problem not being the character, but the place where the convention is held. I mean some of the theatre work (and conventions held there are recorded for the completion) while some don't. I'd suggest to try it on the very first basic neighborhoods and only using the default included theaters and stadiums. Sorry for not being able to help you more.