When Joseph is in prison during the rain scene, he is wearing a white kilt, but when the camera is zooming out through the opening of the cell, he is wearing a red kilt.
One of Joseph's brothers has a hat on inside a tent, then they all walk outside and it shows that same brother with his hat off, then he puts it on.
When Joseph is inspecting the scale from the horse trader, he only lifts the bag of silver and the weights. The extra pieces of silver put on the scale by Potiphar to balance it seem to have suddenly disappeared.
When Asenath is approaching the prison with food for Joseph, she is wearing sandals, but as she kneels to lower the food through the grate, her feet are bare.
Multiple differences between the movie and its original source material. Changes made when another medium is adapted into a movie are, by policy, not considered goofs. The movie even begins with a disclaimer that "artistic and historical license have been taken".
Sunflowers are featured often within the movie, usually in connection with Joseph's mother, Rachel. However, sunflowers are native to the Americas, and did not grow elsewhere until European explorers brought seeds back with them during the 16th century.
In the Beginning of the song More then you take, there's a close up of Joseph's head and shoulders. His headdress is being his shoulders while his arms and shoulders are white. When he Stands up the headdress is on his shoulders and his arms and shoulders went to his regular skin color.