During the final derby scene as Kiddie Car goes to help Phantom Fox, the camera switches from a view inside Kiddie Car to a long shot. Bruno the St. Bernard has now been replaced with a obvious stuffed dog that's supposed to look like a St. Bernard.
When Blarney Stone lands on Max Roca's limo during the demolition derby scene, chains/straps are visible, linking the two cars together to keep the top car from falling off.
During the climactic demolition derby at the warehouse, Dr. Rheems yells that Roca is getting away. At that point, Roca was still a mystery man to everyone. Nobody knew his name. Earlier in the film when the federal investigators were meeting with all the ladies for the first time, Agent Voorhees told them "The big man in this county is Max Roca"
However there was enough time while "staking out the place" while they waited for everyone to show up to be filled in on the plot easy enough.
Why would Howard's mother not recognize the Shortcakes when they showed up at Jane and Howard's reception. She told them no gypsies are allowed. And why were NONE of the other people from their church at the reception.