By Courtney Potter Bedknobs and Broomsticks reunited the creative team behind Disney’s blockbuster Mary Poppins—including director Robert Stevenson; producer and writer Bill Walsh; co-writer Don DaGradi; art director Peter Ellenshaw; special effects technician Eustace Lycett; and the award-winning songwriting team of Robert B. and Richard M. Sherman. Based on characters from a novel by Mary …