About the only legitimate beefs that he has anymore are with Dave Gibbons, who made a ton of money off of the Watchmen movie (and even got to be in it), without mentioning Alan Moore and basically cutting ties with him, and DC comics in general, which has CONTINUALLY fucked Moore over. There was a point they were buying out any company he was working for just to keep him making DC stuff.Read his work, and his comments on anyone in the industry. Considering how much of his work is based on or about other peoples creations (~98%) he really has no leg to stand on when he accuses the entire industry of just ripping off his work and characters. Especially when he claims to have not read anything in the last 20 years (on accounts of everyone being hacks who are just copying him I suppose).
As for the sexist thing, I just gather it from the way he writes his women in the stuff of his I've read. It's not quite Frank Miller bad, but man it's close.
Aside from those two though, I think Alan Moore needs to shut the fuck up. He keeps harping on how everyone in the industry needs to grow some balls and make original work, without recognizing that the only reason Alan Moore gets to make original work is because he hit it big with something that originally starred someone else's characters (which were taken from him when it was apparent what he was writing). If Watchmen had kept the Charlton Comics characters instead of the new ones, he wouldn't be nearly as well known or as successful.
Or to put it simply, not everyone is as lucky as Alan Moore. He's an amazing talent but he got lucky with Watchmen.