Ive actually finished that game in dolphin, i can tell you that emulation is almost perfect. Sometimes sound got wrong. And theres a friggin bug that wont allow you to grab boxes. But u can still play it to full. Try using a later SVN build, i used SVN 3286.if u have a little graphic card, like me, you can also try setting hardware rendering to minimum, specially the anti allaising filter gap. Other thing u can do is to set graphic configuration of your computer to minimum as well, hope i helped you
PS: sry about my english
PS: sry about my english