When the owner of the frog gets thrown out of the talent agency, there's a hand-print on the wall to the side of the door he is thrown from. In the next shot it's gone.
When the construction worker is imitating the frog in the talent agency, he's initially holding his hat, then throws his hands up in the air. When his hands come back down, his hat has disappeared. When he is thrown out of the agent's office to the hallway, his hat is back on his head.
When the curtain falls on the construction worker, pushing him to the ground, he's on the side of the stage. As the audience starts throwing watermelons, heads of lettuce and other vegetables at the construction worker's head, he's now in the center of the stage.
Everytime the frogs starts singing there is music that starts playing although there is no source for the music.