You will miss the sing along and probably the start of the movie, if that doesn't bother you then go for it. People are milling about during the movie so late arrivals are not a big deal. As for getting there, walk from the HDDR to the bus stop, get on the Orange Outpost bus and tell the driver where you are going, the driver will make sure he annonces the stop(I think it is the first one). The path to the show is to the left of the bus.