It's like they (the 35 reported screenwriters that worked on this film and others involved) thought the effort with the production design and some prop gags was enough so they didn't bother with a decent story. Siskel & Ebert's review of this was spot on. The story is kind of adult, but it lacks a crescendo, and isn't deep enough or interesting enough to be entertaining. And there are many aspects of the story that wouldn't be engaging for kids. It seems like they tried to tick both boxes, like the best family movies do, but they didn't succeed.