(for instance, if the girl was a robot since the time the doctor "rescued" her, why did she help him escape? Why didn't she try to stop him from destroying the factory?)
I agree. I had the same problem with that too. The way I rationalize it now, after watching it numerous times
, is that she doesn't seem to get hostile until the Silver Shamrock commericial is played on the car radio, maybe that activated some kind of programming in her. Not saying it makes complete sense, but that's the way I look at.
It's definitely a flawed film, but fun to watch it.