I think that Joe Public is already scared witless enough of being involved with the JWs. I don't think a film is going to strengthen their resolve that much more.
Remember how people used to react to us when we knocked on their doors? JWs are seen as fookin' weirdo's. Pretty good judgement IMO.
Even the blinking Moonies still get converts.
JW's will sadly ALWAYS get converts as long as they exist as an org'.
Our efforts through channels such as this forum will be just as effective in deterring the unwary.
Peace
Lowden