Complex sentence: The Muppets at Walt Disney World is an attraction starring Jim Henson's Muppets, and this is the last Muppets project that Jim Henson worked on before his death in 1990.
Split into simpler sentences: The Muppets at Walt Disney World is an attraction starring Jim Henson's Muppets. Apparently, This is the last Muppets project before Jim Henson's death in 1990.