But it's not true that it's the first Star Wars spin-off film. Ewoks: Caravan of Courage and Ewoks: Battle of Endor were the first live action spin-offs in the Star Wars universe but non-canon. The Star Wars Holiday Special doesn't count as it was a cancelled film.
Been a fan since 1977, and this is the only Star Wars film that I saw only one time in the theater. It had its moments, but not enough to make me want to see it again.