Summer Days was apparently not a particularly well made game and got bad reviews in Japan. I know there's no patch for it, and don't think there's one for School Days either.

Also it seems the final episode AT-X aired was in fact edited, other than the obvious red->black blood they apparently added or replaced material with flash backs and removed some of the sound effects, hopefully this is the reason the the Itou and Sekai scenes seemed so choppy. When it makes it to DVD I'll definately get it to experience Makoto get owned in it's original glory.